Digital PDFs

AA-LA87A-TE

December 1988

193 pages

Original

7.0MB

Document:	VMS 5.0 System Dump Analyzer Utility Manual 198804
Order Number:	AA-LA87A-TE
Revision:
Pages:	193
Original Filename:	http://bitsavers.org/pdf/dec/vax/vms/5.0/AA-LA87A-TE_VMS_5.0_System_Dump_Analyzer_Utility_Manual_198804.pdf

OCR Text

VMS

digital

VMS System Dump Analyzer Utility Manual

Order Number AA-LA87A-TE

VMS System Dump
Analyzer Utility Manual
Order Number: AA-LA87 A-TE

April 1988
This manual explains how to use the System Dump Analyzer (SDA) to
investigate system failures and examine a running system.

Revision/Update Information:

This book supersedes the VAX/VMS
System Dump Analyzer Reference
Manual for VAX/VMS Version 4.4,
published April 1986.

Operating System and Version: VMS Version 5.0

digital equipment corporation
maynard, massachusetts

April 1988
The information in this document is subject to change without notice and should
not be construed as a commitment by Digital Equipment Corporation. Digital
Equipment Corporation assumes no responsibility for any errors that may appear
in this document.
The software described in this document is furnished under a license and may be
used or copied only in accordance with the terms of such license.
No responsibility is assumed for the use or reliability of software on equipment
that is not supplied by Digital Equipment Corporation or its affiliated companies.
Copyright © 1988 by Digital Equipment Corporation
All Rights Reserved.
Printed in U.S.A.
The postpaid READER'S COMMENTS form on the last page of this document
requests the user's critical evaluation to assist in preparing future documentation.
The following are trademarks of Digital Equipment Corporation:
DEC
DEC/CMS
DEC/MMS
DECnet
DECsystem-10
DECSYSTEM-20
DECUS
DECwriter

DIBOL
EduSystem
IAS
MASS BUS
PDP
PDT
RSTS
RSX

UNIBUS
VAX
VAXcluster
VMS
VT

~urnua~u™
ZK4556

HOW TO ORDER ADDITIONAL DOCUMENTATION
DIRECT MAIL ORDERS
USA & PUERTO Rico*

CANADA

INTERNATIONAL

Digital Equipment Corporation
P.O. Box CS2008
Nashua, New Hampshire
03061

Digital Equipment
of Canada Ltd.
100 Herzberg Road
Kanata, Ontario K2K 2A6
Attn: Direct Order Desk

Digital Equipment Corporation
PSG Business Manager
c/o Digital' s local subsidiary
or approved distributor

In Continental USA and Puerto Rico call 800-258-1710.
In New Hampshire, Alaska, and Hawaii call 603-884-6660.
In Canada call 800-267-6215.
*Any prepaid order from Puerto Rico must be placed with the local Digital subsidiary (809-754-7575).
Internal orders should be placed through the Software Distribution Center (SOC), Digital Equipment
Corporation, Westminster, Massachusetts 01473.

Production Note
This book was produced with the VAX DOCUMENT electronic publishing
system, a software tool developed and sold by DIGITAL. In this system,
writers use an ASCII text editor to create source files containing text and
English-like code; this code labels the structural elements of the document,
such as chapters, paragraphs, and tables. The VAX DOCUMENT software,
which runs on the VMS operating system, interprets the code to format the
text, generate a table of contents and index, and paginate the entire document.
Writers can print the document on the terminal or line printer, or they can use
DIGITAL-supported devices, such as the LN03 laser printer and PostScript®
printers (PrintServer 40 or LN03R ScriptPrinter), to produce a typeset-quality
copy containing integrated graphics.

PostScript is a trademark of Adobe Systems, Inc.

Contents
PREFACE

NEW AND CHANGED FEATURES

xiii

SDA Description

SDA-1

SYSTEM MANAGEMENT AND SDA
The System Dump File
Dump File Style• SDA-4
Saving System Dumps
Invoking SDA in the Site-Specific Startup Command
Procedure

SDA-2
SDA-2

2.3
2.4
2.5

ANALYZING A SYSTEM DUMP
Requirements
Invoking SDA
Mapping the Contents of the Dump File
Building the SDA Symbol Table
Executing the SDA Initialization File (SDA$1NIT)

SDA-6
SDA-6
SDA-6
SDA-7
SDA-7
SDA-8

ANALYZING A RUNNING SYSTEM

SDA-8

SDA CONTEXT

SDA-9

SDA COMMAND FORMAT
General Command Format
Expressions
Radix Operators• SDA-12
Arithmetic and Logical Operators • SDA-12
Precedence Operators• SDA-13
Symbols • SDA-13

SDA-10
SDA-11
SDA-11

INVESTIGATING SYSTEM FAILURES
General Procedure for Analyzing System Failures
Fatal Bugcheck Conditions
Fatal Exceptions • SDA-16
Illegal Page Faults• SDA-19

SDA-15
SDA-15
SDA-16

1
1.1

1. 1. 1
1.2
1.3

2
2.1

2.2

5.1
5.2

5.2.1
5.2.2
5.2.3
5.2.4
6
6.1
6.2

6.2.1
6.2.2

SDA-4
SDA-5

Contents

SDA-21
SDA-21
SDA-21
SDA-23

7.4.3

A SAMPLE SYSTEM FAILURE
Identifying the Bugcheck
Identifying the Exception
Locating the Source of the Exception
Finding the Driver by Using the Program Counter • SDA-23
Calculating the Offset into the Driver's Program
Section • SDA-24
Finding the Problem Within the Routine
Examining the Routine • SDA-25
Checking the Values of Key Variables • SDA-26
Identifying and Fixing the Defective Code • SDA-27

8
8.1
8.2

INDUCING A SYSTEM FAILURE
Meeting Crash Dump Requirements
Examples of How to Cause System Failures

SDA-28
SDA-28
SDA-29

7
7.1
7.2
7.3

7.3.1
7.3.2
7.4
7.4.1
7.4.2

SDA Usage Summary

SDA-32

SDA Qualifiers

SDA-34
/CRASH_DUMP
/RELEASE
/SYMBOL
/SYSTEM

SDA-35
SDA-36
SDA-37
SDA-38

SDA Commands

SDA-39
@(EXECUTE PROCEDURE)
ATTACH
COPY
DEFINE
EVALUATE
EXAMINE
EXIT
FORMAT
HELP
READ
REPEAT
SEARCH
SET CPU
SET LOG
SET OUTPUT
SET PROCESS
SET RMS
SHOW CALL_FRAME
SHOW CLUSTER

SDA-24

SDA-40
SDA-41
SDA-42
SDA-43
SDA-48
SDA-51
SDA-55
SDA-56
SDA-58
SDA-59
SDA-64
SDA-66
SDA-68
SDA-71
SDA-72
SDA-73
SDA-76
SDA-79
SDA-82

Contents

SHOW CONNECTIONS
SHOW CPU
SHOW CRASH
SHOW DEVICE
SHOW EXECUTIVE
SHOW HEADER
SHOW LOCK
SHOW PAGE_TABLE
SHOW PFN_DATA
SHOW POOL
SHOW PORTS
SHOW PROCESS
SHOW RESOURCE
SHOW RMS
SHOW RSPID
SHOW SPINLOCKS
SHOW STACK
SHOW SUMMARY
SHOW SYMBOL
SPAWN
VALIDATE QUEUE

SDA-87
SDA-89
SDA-93
SDA-98.
SDA-104
SDA-106
SDA-108
SDA-111
SDA-115
SDA-118
SDA-123
SDA-126
SDA-143
SDA-147
SDA-148
SDA-150
SDA-157
SDA-159
SDA-161
SDA-162
SDA-164

INDEX

FIGURES
SDA-1

First Argument List on the Stack

SDA-17

SDA-2

Mechanism Array

SDA-17

SDA-3

Signal Array

SDA-18

SDA-4

Stack Following an Illegal Page-Fault Error

SDA-20

SDA-5

Call Frame

SDA-80

SDA-1

Comparison of Full and Subset Dump Files

SDA-4

SDA-2

SDA Operators

SDA-12

SDA-3

SDA Symbols

SDA-13

SDA-4

Modules Containing Global Symbols Used by SDA

SDA-60

SDA-5

Modules Defining Global Locations Within the Executive
Image

SDA-60

SET RMS Command Keywords for Displaying Process
RMS Information

SDA-76

TABLES

SDA-6

vii

Contents

SDA-7

Contents of the SHOW LOCK and
SHOW PROCESS/LOCKS Displays

SDA-108

Virtual Page Information in the SHOW PAGE_TABLE
Display

SDA-112

Physical Page Information in the SHOW PAGE_TABLE
Display

SDA-113

Page Frame Number Information in the
SHOW PFN_DATA Display

SDA-116

Process Section Table Entry Information in the
SHOW PROCESS Display

SDA-130

Process 1/0 Channel Information in the SHOW PROCESS
Display

SDA-131

SDA-13

Resource Information in the SHOW RESOURCE Display

SDA-143

SDA-14

Static Spin Locks

SDA-151

SDA-15

Process Information in the SHOW SUMMARY Display

SDA-8
SDA-9
SDA-10
SDA-11
SDA-12

viii

SDA-159

Preface
Intended Audience
The VMS System Dump Analyzer Utility Manual is primarily intended for the
system programmer who must investigate the causes of system failures and
debug kernel mode code, such as a device driver. This programmer should
possess some knowledge of VMS data structures to properly interpret the
results of System Dump Analyzer (SDA) commands.
The VMS System Dump Analyzer Utility Manual also includes information
required by the system manager in order to maintain the system resources
necessary to capture and store system crash dumps. Those who need to
determine the cause of a hung process or improve system performance may
refer to this manual for instructions for using SDA to analyze a running
system.

Document Structure
The VMS System Dump Analyzer Utility Manual includes the following four
sections:
•

The first section provides an introduction to the functions of the System
Dump Analyzer (SDA), a description of its features, a discussion of
key concepts, and an illustration of its use. It includes instructions for
maintaining the optimal environment for the analysis of system failures,
and notes the requirements for processes invoking SDA.

•

The second section outlines the following aspects of SDA usage:
Invoking SDA
Exiting from SDA
Recording the output of an SDA session
Required privileges

•

The third section describes those qualifiers to the AN AL YZE command
that govern the behavior of SDA.

•

The last section describes the function, format, and parameters of each
SDA command. It also provides examples of situations in which specific
commands are useful.

Preface

Associated Documents
The VMS System Dump Analyzer Utility Manual presumes an understanding of
the material discussed in the following documents:
•

VMS naming conventions as described in the Guide to Creating VMS
Modular Procedures

•

VMS operational concepts as described in the Introduction to VMS System
Management, Guide to Setting Up a VMS System, Guide to Maintaining a
VMS System, and Guide to VMS Performance Management

•

VMS data structures and concepts as described in the VAX/VMS Internals
and Data Structures and the VMS Device Support Manual

Investigators of VAXcluster failures will find the discussions in the VMS
VAXcluster Manual and the VMS Show Cluster Utility Manual helpful in
understanding the output of several SDA commands.

Conventions
Typographical conventions used in this book include the following:

•

The term quotation marks" refers to double quotation marks ( "). The
term apostrophe" refers to a single quotation mark ( ').

•

Terms that serve as parameters to commands and qualifiers appear in
boldface in the text of the manual. For example:

The value csid is the cluster system identification number (CSID) of the
node to be displayed.
•

Terms that serve as variables in a mathematical expression or a file
specification appear in italic print:
The default file specification is as follows:

SYS$DISK:[default-dir]SYSDUMP .DMP
SYS$DISK and [default-dir] represent the disk and
directory specified in your last SET DEFAULT
command.
•

In format descriptions, brackets indicate that the enclosed item is optional.
(Brackets are not, however, optional in the syntax of a directory name in
a file specification or in the syntax of a substring specification in an
assignment statement.)
FORMAT[/ qualifier] location

•

In format descriptions, stacked lists of items are enclosed in either braces
or brackets. In either case, the parameters or qualifiers in the stack are
optional in the syntax of the command.
When braces enclose the list, you can include only one of the items from
the list in the command. For example:

/CONDITION_VALUE }
EVALUATE

{

;~it

/SYMBOLS

expression

Preface

When brackets enclose the list, you can generally include more than
one item from the stack in the command. Incompatible qualifiers and
parameters are given special mention in the syntax descriptions.
range
/ALL

SHOW POOL

•

/FREE
/HEADER

]

[ /SUMMARY
/TYPE=block-type

/IRP
/LRP

/NO NPAGED
/PAGED
/SRP

In format descriptions, a horizontal ellipsis indicates that additional
parameters, values, or information can be entered. For example:
SET RMS= (option{, ...])

In examples, a horizontal ellipsis also indicates that columns of
information have been omitted from the display. For example:
SDA> SHOW HEADER
Dump file header
7FF03944
00000000
00000000
00020000

•

00000000
80185200
00000000
00000000

................. N... D9 .. 00000000
.R ....................... 00000020
. . . . . . . . . . . . . . . . . . . . . . . . . 00000040
. . . . . . . . . . . . . . . . . . . . . . . . . 00000060

In format descriptions, parentheses indicate that you should enclose
the choices you select in parentheses if you select more than one. For
example:
SET RMS = (option[, ...])

•

In interactive examples, all output lines or prompting characters that
the system prints or displays appear in black letters. All user-entered
commands are shown in red letters. For example:
$ ANALYZE/CRASH_DUMP SYS$SYSTEM:SYSDUMP.DMP
$ ANAL/CRASH SYS$SYSTEM

•

In interactive examples, a symbol with a 1- to 6-character abbreviation
indicates that you press a key on the terminal, for example, IRET I.

•

In interactive examples, the symbol ICTRL/xl indicates that you must press
the key labeled CTRL while you simultaneously press another key: for
instance, lcTRL/CL

•

In interactive examples, a vertical ellipsis means either that not all the
data that the system would display in response to the particular command
is shown or that not all the data a user would enter is shown. For
example:
SDA> READ SYS$SYSTEM:SYSDEF.STB
SDA> FORMAT 800B81FO
800B81FO
UCB$L_FQFL
UCB$L_RQFL

UCB$L_FIRST

80000F10

8002CAOO

New and Changed Features
This manual applies to Version 5.0 of the VMS operating system.
The following list summarizes the major changes to the previous edition of
the manuai.
•

The context of certain SDA commands now depends on the definition of
both the SDA current process and the SDA current CPU. The descriptions
of the following commands have been altered to reflect the behavior of
SDA in analyzing a Version 5.0 multiprocessor system failure:
SET PROCESS
SHOW CRASH
SHOW PROCESS
SHOW STACK
The following new commands have been added to the manual:
SET CPU

Selects a processor to become the SDA current CPU

SHOW CPU

Displays information about the state of a processor at
the time of the system failure

SHOW SPINLOCKS

Displays the data structures that provide system
synchronization in a VAX multiprocessing system

Section 4 discusses the implications of changing SDA CPU and process
context.
•

Version 5.0 changes in the composition of the VMS executive and its
corresponding loaded images may be evident in the names of certain
symbols displayed in the output of various commands (such as SHOW
STACK) in an SDA session. To aid in identifying locations within the
executive image, SDA provides the following features:
A new command, SHOW EXECUTIVE, lists the location and size of
·each loadable image that is part of the Version 5.0 VMS executive.
The /EXECUTIVE qualifier has been added to the READ command to
facilitate the loading of symbols into the SDA symbol table to further
identify global locations within the VMS executive.
The description of the SHOW EXECUTIVE command includes a
discussion of the components of the Version 5.0 VMS executive.

•

Several options have been added to the SET RMS and SHOW
PROCESS /RMS commands, allowing the display of the following
RMS structures: recovery unit block (RUB), recovery unit stream block
(RUSB), recovery unit file block (RUFB), shared file synchronization block
(SFSB), global buffer synchronization block (GFSB), and network work
area (NWA). These commands also allow the display of the structures
associated with process 1/0 by means of the [NO]PIO option.

•

When invoked, SDA reads into its symbol table a subset of
SYS$SYSTEM:SYSDEF.STB, called SYS$SYSTEM:REQSYSDEF.STB,
that it requires to identify certain locations in memory. SDA reads
REQSYSDEF.STB in addition to reading the system symbol table
xiii

New and Changed Features

(SYS$SYSTEM:SYS.STB). See Section 2.4 for a description of this
procedure.

xiv

•

The symbol MP and the symbol table file (MP.STB) are no longer
available to SDA in Version 5.0.

•

Instructions on inducing a system failure on newer VAX processors have
been added to Section 8.

•

A new system parameter, DUMPSTYLE, when set, allows a system whose
memory capacity exceeds the disk space available for storing crash dumps
to preserve a subset of memory contents for analysis by SDA. (See the
discussion in Section 1.1.1 for a discussion of this feature.)

•

Various minor revisions, as well as some reorganization of material, may
be apparent throughout the manual. In addition, some examples have
been added and others have been corrected to better reflect the operation
of SDA under VMS Version 5.0.

SDA Description
When a fatal error causes the system to fail, the VMS operating system
copies the contents of memory to a system dump file, recording the hardware
context of each processor in the system as well. The System Dump Analyzer
(SDA) provides a means of interpreting the contents of this file, thus enabling
you to examine the status of each processor at the time of the failure and
investigate the probable causes of the crash. To do so, you invoke SDA by
means of the DCL command ANALYZE/CRASH-DUMP.
You can use SDA commands to perform the following operations:
•

Direct (or echo) the output of an SDA session to a file or device (SET
OUTPUT or SET LOG)

•

Display the condition of the operating system and the hardware context
of each processor in the system at the time of the crash (SHOW CRASH)

•

Select a specific processor in a multiprocessing system as the subject of
analysis (SET CPU).

•

Display the contents of a specific process stack or the interrupt stack of a
specific processor (SHOW STACK)

•

Format a call frame from a stack location (SHOW CALL _FRAME)

•

Read a set of global symbols into the SDA symbol table (READ)

•

Define symbols to represent values or locations in memory and add them
to the SDA symbol table (DEFINE)

•

Evaluate an expression in hexadecimal and decimal, interpreting its value
as a symbol, a condition value, a page-table entry (PTE), or a processor
status longword (PSL) (EVALUATE)

•

Examine the contents of memory locations, optionally interpreting them
as VAX MACRO instructions, a PTE, or a PSL (EXAMINE)

•

Display device status as reflected in system data structures (SHOW
DEVICE)

•

Format system data structures (FORMAT)

•

Validate the integrity of the links in a queue (VALIDATE)

•

Display a summary of all processes on the system (SHOW SUMMARY)

•

Examine the memory of any process (SHOW PROCESS)

•

Display the RMS data structures of a process (SHOW PROCESS /RMS)

•

Display memory management data structures (SHOW POOL, SHOW
PFN_DATA, SHOW PAGE_TABLE)

•

Display lock management data structures (SHOW RESOURCE, SHOW
LOCK)

•

Display VAXcluster management data structures (SHOW CLUSTER,
SHOW CONNECTIONS, SHOW RSPID, SHOW PORTS)

•

Display multiprocessor synchronization information (SHOW
SPINLOCKS)
SDA-1

SDA Description

•

Display the layout of the loadable executive images (SHOW EXECUTIVE)

•

Copy the system dump file (COPY)

•

Define keys to invoke SDA commands (DEFINE/KEY)

•

Search memory for a given value (SEARCH)

Although SDA provides a great deal of information, it does not analyze all
the control blocks and data contained in memory. For this reason, in the
event of system failure it is extremely important that you send DIGITAL
a Software Performance Report (SPR) and a copy of the system dump file
written at the time of the failure.
You can also invoke SDA to analyze a running system, using the DCL
command ANALYZE/SYSTEM. Most SDA commands generate useful output
in this mode of operation. Although the analysis of a running system may
be instructive, you should undertake such an operation with the caution that
system context, process context, and a processor's hardware context remain
fluid during any given display. A user in a multiprocessing environment
should especially note that it is highly possible that a process running SDA
could be rescheduled to a different processor frequently during analysis. It is
thus advisable to avoid the examination of the hardware context of processors
in a running system.

System Management and SDA
The system manager must ensure that the system writes a dump file
whenever the system fails. The manager must also see that the dump file
is large enough to contain all the information to be saved, and that the dump
file is saved for analysis. The following sections describe these tasks.

1 .1

The System Dump File
The VMS operating system will attempt to write information into the system
dump file only if the system parameter DUMPBUG is set. 1 If DUMPBUG is
set and the operating system fails, VMS writes the contents of the error-log
buffers, processor registers, and physical memory into the system dump file,
overwriting its previous contents.
If the system dump file is too small, VMS cannot copy all of memory to the

file when a system failure occurs. For most systems, this means that the
system's page table (SPT) is not included in the dump. SDA cannot analyze a
dump unless the SPT is included in the dump in its entirety.
The file SYS$SYSTEM:SYSDUMP .DMP is furnished as an empty file in
the VMS software distribution kit. In order to successfully store a crash
dump, you must make SYS$SYSTEM:SYSDUMP.DMP large enough to
hold all the information to be written when the system fails. If this is
not possible, you can have VMS write dumps into the system paging file,
SYS$SYSTEM:PAGEFILE.SYS. You can enlarge or adjust the size of either of
these files by using the CREATE command of the System Generation Utility
(SYSGEN), as described in the VMS System Generation Utility Manual.

The DUMPBUG parameter is set by default. To examine and/or change its value, consult the VMS System

Generation Utility Manual.

SDA-2

SDA Description

To calculate the correct size for SYS$SYSTEM:SYSDUMP.DMP, use the
following formula:
size-in-blocks(SYS$SYSTEM:SYSDUMP.DMP)
= size-in-pages(physical-memory)
+ number-of-error-log-buffers
+ 1

You can use the DCL command SHOW MEMORY to determine the total size
of physical memory on your system. In addition, you must account for any
MA780 multiport memory installed on your system. There are a variable
number of error log buffers in any given VAX system, depending upon the
setting of the ERRORLOGBUFFERS system parameter. (See the VMS System
Generation Utility Manual for additional information about this parameter.)
If SYS$SYSTEM:SYSDUMP.DMP does not exist, the VMS operating system

writes the dump of physical memory into SYS$SYSTEM:PAGEFILE.SYS, the
system's paging file, overwriting the contents of that file. If the SAVEDUMP
system parameter is set, the dump file is retained in PAGEFILE.SYS when the
system is booted. If it is clear, VMS uses the entire paging file for paging and
any dump written to the paging file is lost. 2
To calculate the minimum size for SYS$SYSTEM:PAGEFILE.SYS, use the
following formula:
size-in-blocks(SYS$SYSTEM:PAGEFILE.SYS)
= size-in-pages(physical-memory)
+ number-of-error-log-buffers
+ 1
+ 1000

Note that this formula calculates the minimum size requirement for saving
a dump in the system's paging file. Generally, the paging file must be
larger than this for most systems to avoid hanging the system (see the
Guide to Setting Up a VMS System). Use of SYS$SYSTEM:PAGEFILE.SYS
to take system crash dumps presumes that you will later free the
space occupied by the dump for use by the pager. Generally, you
include SDA commands in the site-specific startup command procedure
(SYS$MANAGER:SYSTARTUP.COM) that do this. Otherwise, your system
may hang during the startup procedure.
A common method for doing this is to copy the dump from
SYS$SYSTEM:P AGEFILE.SYS to another file, using the SDA COPY
command. Although the DCL COPY command can also be used to copy
a dump file, only the SDA COPY command causes the pages occupied by the
dump to be freed from the system's paging file.
Occasionally, you may want to free the pages in the paging file that are
taken up by the dump without having to copy the dump elsewhere. When
you issue the ANALYZE/CRASH_DUMP /RELEASE command, SDA
immediately releases the pages to be used for system paging, effectively
deleting the dump. Note that this command does not allow you to analyze
the dump before deleting it.

The SAVEDUMP parameter is clear by default. To examine and/or change its value, consult the VMS System

Generation Utility Manual.

SDA-3

SDA Description

1.1.1

Dump File Style
In certain VAX system configurations, it may be impossible to preserve the
entire contents of memory in a disk file. For instance, a large memory system
or a system with small disk capacity may not be able to supply enough disk
space for a full memory dump. In normal circumstances, if the system dump
file cannot accommodate all of memory, SDA cannot analyze the dump.

To preserve those portions of memory that contain information most useful
in determining the causes of system failures, a system manager sets the static
system parameter DUMPSTYLE to 1. When the DUMPSTYLE parameter is
set, AUTOGEN attempts to create a dump file large enough to contain ample
information for SDA to analyze a failure. When the DUMPSTYLE parameter
is clear, the default case, AUTOGEN attempts to create a dump file large
enough to contain all of physical memory.
A comparison of full and subset style dump files appears in Table SDA-1.
Table SDA-1

1.2

Comparison of Full and Subset Dump Files
Full

Subset

Available
Information

Complete contents of physical memory
in use, stored in order of increasing
physical address (for instance, system
and global page tables are stored last).

System page table, global page table, system
space memory, and process and control
regions (plus global pages) for all saved
processes.

Unavailable
Information

Contents of paged-out memory at the
time of the crash.

Contents of paged-out memory at the time
of the crash, process and control regions of
unsaved processes, and memory not mapped
by a page table (such as the free and modified
lists).

SDA Command
Limitations

None.

The following commands are not useful
for unsaved processes: SHOW PROCESS
/CHANNELS, SHOW PROCESS/RMS, SHOW
ST ACK, and SHOW SUMMARY /IMAGE.

Saving System Dumps
Every time the operating system writes information to the system dump file,
it writes over whatever was previously stored in the file. For this reason, the

system manager should save the contents of the file after a system failure has
occurred.
The system manager can use the SDA COPY command or the DCL COPY
command. Either command can be used in your site-specific startup
procedure, but the SDA COPY command is preferred because it marks
the dump file as copied. As mentioned earlier, this is particularly important
if the dump was written into the paging file, SYS$SYSTEM:P AGEFILE.SYS,
because it releases those pages occupied by the dump to the pager.
Because system dump files are set to NO BACKUP, the Backup Utility
(BACKUP) does not copy them to tape unless you use the qualifier
/IGNORE=NOBACKUP when invoking BACKUP. When you use the SDA
COPY command to copy the system dump file to another file, VMS does not
set the new file to NO BACKUP.

SDA-4

SDA Description

As included in the VMS distribution kit, SYS$SYSTEM:SYSDUMP. DMP is
protected against world access. Because a dump file can contain privileged
information, it is a good idea for the system manager to continue to protect
dump files from universal read access.

1 .3

Invoking SDA in the Site-Specific Startup Command Procedure
Because a listing of the SDA output is an important source of information
in determining the cause of a system failure, it is a good idea to have SDA
produce such a listing after every failure. The system manager can ensure the
creation of a listing by modifying the site-specific startup command procedure
SYS$:tviANAGER:SYSTARTUP .COM so that it invokes SDA when the system
is booted.
When invoked in the site-specific startup procedure, SDA executes the
specified commands only if the system is booting immediately after a system
failure. SDA examines a flag in the dump file's header that indicates whether
it has already processed the file. If the flag is set, SDA merely exits. If
the flag is clear, SDA executes the specified commands and sets the flag.
This flag is clear when the operating system initially writes a crash dump,
except for those resulting from an operator-requested shutdown (for instance,
SYS$SYSTEM:OPCCRASH.COM or SYS$SYSTEM:SHUTDOWN.COM).
The following example shows typical commands that might be added to your
site-specific startup command procedure to produce an SDA listing after each
failure.
$ !
$ !
Print dump listing if system just failed
$ !
$ ANALYZE/CRASH_DUMP SYS$SYSTEM:SYSDUMP.DMP
COPY SYS$SYSTEM:SAVEDUMP.DMP
Save dump file
SET OUTPUT LPAO:SYSDUMP.LIS
! Create listing file
SHOW CRASH
Display crash
information
SHOW STACK
Show current stack
SHOW SUMMARY
List all active
processes
SHOW PROCESS/PCB/PHD/REG
Display current process
SHOW SYMBOL/ALL
Print system symbol
! table
EXIT

The COPY command in the preceding example saves the contents of the file
SYS$SYSTEM:SYSDUMP.DMP. If your system's startup command file does
not save a copy of the contents of this file, this crash dump information will
be lost in the next system failure, when the system saves the information on
the new failure, overwriting the contents of SYS$SYSTEM:SYSDUMP.DMP.
If you are using the SYS$SYSTEM:P AGEFILE.SYS as the crash dump file,

you must include SDA commands in SYS$MANAGER:SYSTARTUP.COM
that free the space occupied by the dump so that the pager can use it. For
instance:
$ ANALYZE/CRASH_DUMP SYS$SYSTEM:PAGEFILE.SYS

COPY dump_f ilespec
EXIT

SDA-5

SDA Description

Analyzing a System Dump
SDA performs certain tasks prior to bringing a dump into memory, presenting
its initial displays, and accepting command input. This section describes those
tasks, which include
•

Verifying that the process invoking it is suitably privileged to read the
dump file

•

Mapping the contents of the specified dump file

•

Reading the system symbol tables (SYS$SYSTEM:SYS.STB and
SYS$SYSTEM:REQSYSDEF.STB)

•

Executing the commands in the SDA initialization file

For detailed information on the investigation of a system failure, see
Section 6.

2.1

Requirements
In order to be able to analyze a dump file, your process must have

2.2

•

Read access both to the file that contains the dump and to copies of the
symbol tables SYS$SYSTEM:SYS.STB (the system symbol table) and
SYS$SYSTEM:REQSYSDEF.STB (the required subset of the symbols
in the file SYSDEF.STB). SDA reads these tables by default. As
included in the VMS distribution kit, SYS$SYSTEM:SYSDUMP.DMP,
SYS$SYSTEM:SYS.STB, and SYS$SYSTEM:REQSYSDEF.STB are
protected against world access. Either a system UIC or SYSPRV privilege
thus is needed for a process to read the dump file.

•

Sufficient virtual address space for SDA to map the entire dump and any
required symbol tables, plus space to be used for the stacks. To ensure
that SDA has the correct amount of virtual address space, the value of
the system parameter VIRTUALP AGECNT must be larger than the size of
the system's dump file by approximately 3000 pages. Further increases in
the parameter may be required if your particular installation places extra
heavy demands upon the virtual address space of the process.

Invoking SDA
If your process satisfies these conditions, you can issue the DCL command
ANALYZE/CRASH_DUMP to invoke SDA. If you do not specify the name
of a dump file in the command, SDA prompts you for the name of the file, as
follows:
$ ANALYZE/CRASH_DUMP
_Dump File:

The default file specification is as follows:

SYS$DISK:[default-dir]SYSDVMP.DMP
SYS$DISK and [default-dir] represent the disk and directory specified in your
last SET DEFAULT command.

SDA-6

SDA Description

2.3

Mapping the Contents of the Dump File
SDA first att~mpts to map the contents of physical memory as stored in the
specified dump file. To do this, it must first locate the system page table
(SPT) among its contents. The SPT contains one entry for each page of
system virtual address space.
The SPT appears at the largest physical addresses in a typical VMS
configuration. As a result, if a dump file is too small, the SPT cannot be
written to it in the event of system failure.
If SDA cannot find the SPT in the dump file, it displays either of the following
messages:
%SDA-E-SPTNOTFND, system page table not found in dump file
%SDA-E-SHORTDUMP, the dump only contains m out of n pages of physical memory

If either of these error messages is displayed, you cannot analyze the crash
dump, but must take steps to ensure that any subsequent dump can be
preserved. To do this, you must increase the size of the dump file as indicated
in Section 1.1 or adjust the system DUMP_STYLE parameter as discussed in
Section 1.1.1.

Under certain conditions, some memory locations might not be saved in the
system dump file. For instance, during halt/restart bugchecks, the contents
of general registers are not preserved. If such a bugcheck occurs, SDA
indicates in the SHOW CRASH display that the contents of the registers were
destroyed. Additionally, if a bugcheck occurs during system initialization, the
contents of the register display may be unreliable. The symptom of such a
bugcheck is a SHOW SUMMARY display that shows no processes or only the
swapper process.
Also, you should note that if you use an SDA command to access a virtual
address that has no corresponding physical address, SDA generates the
following error message:
%SDA-E-NOTINPHYS, 'location' not in physical memory

When analyzing a subset dump file, if you use an SDA command to access a
virtual address that has a corresponding physical address but was not saved
in the dump file, SDA generates the following error message:
%SDA-E-MEMNOTSVD, memory not saved in the dump file

2.4

Building the SDA Symbol Table
After locating and reading the system dump file, SDA attempts to read
the system symbol table file into the SDA symbol table. This file, named
SYS$SYSTEM:SYS.STB by default, contains most of the global symbols used
by the VMS operating system. If SDA cannot find the system symbol table
file-or is given a file that is not a system symbol table in the /SYMBOL
qualifier to the ANALYZE command-it halts with a fatal error. SDA also
reads into its symbol table a subset of SYS$SYSTEM:SYSDEF.STB, called
SYS$SYSTEM:REQSYSDEF.STB, that it requires to identify locations in
memory.

SDA-7

SDA Description

When SDA finishes building its symbol table, it displays a message
identifying itself and the immediate cause of the crash. In the following
example, the cause of the crash was an illegal exception occurring at an IPL
above IPL$_ASTDEL or while using the interrupt stack.
VAX/VMS System dump analyzer
Dump taken on 28-Jan-1989 18:10:09.79
INVEXCEPTN, Exception while above ASTDEL or on interrupt stack

2.5

Executing the SDA Initialization File (SDA$1NIT)
After displaying the crash summary, SDA executes the commands in the SDA
initialization file, if you have established one. SDA refers to its initialization
file by using the logical name SDA$INIT. If SDA cannot find the file defined
as SDA$INIT, it searches for the file SYS$LOGIN:SDA.INIT.
This initialization file can contain SDA commands that read symbols into
SDA's symbol table, define keys, establish a log of SDA commands and
output, or perform other tasks. For instance, you may want to use an SDA
initialization file to augment SDA's symbol table with definitions helpful in
locating system code. If you issue the following command, SDA includes
those symbols that define many of the system's data structures, including
those in the I/O database.
READ SYS$SYSTEM:SYSDEF.STB

You may also find it very helpful to define those symbols that identify the
modules in the images that make up the VMS executive. You can do this by
issuing the following command:
READ/EXECUTIVE SYS$LOADABLE_IMAGES

After SDA has executed the commands in the initialization file, it displays its
prompt, as follows:
SDA>

The SDA> prompt indicates that you can use SDA interactively and enter
SDA commands.

Analyzing a Running System
Occasionally VMS encounters an internal problem that hinders system
performance without causing a system failure. By allowing you to examine
the running system, SDA provides the means to search for the solution to
the problem without disturbing the operating system. For example, you can
use SDA to examine the stack and memory of a process that is stalled in
a scheduler state, such as a miscellaneous wait (MWAIT) or a suspended
(SUSP) state (see the Guide to VMS Performance Management).
If your process has change-mode-to-kernel (CMKRNL) privilege, you can

invoke SDA to examine the system. Use the following DCL command:
$ ANALyzE/SYSTEM

SDA-8

SDA Description

SDA attempts to load the system symbol table (SYS$SYSTEM:SYS.STB) and
symbol table SYS$SYSTEM:REQSYSDEF.STB. It then executes the contents
of any existing SDA initialization file, as it does when invoked to analyze
a crash dump (see Sections 2.4 and 2.5, respectively). SDA subsequently
displays its identification message and prompt, as follows:
VAX/VMS System analyzer
SDA>

The SDA> prompt indicates that you can use SDA interactively and enter
SDA commands. When analyzing a running system, SDA sets its process
context to that of the process running SDA.
If you are undertaking an analysis of a running system, you should take into

account the following considerations:
•

When used in this mode, SDA does not map the entire system, but
instead retrieves only the information it needs to process each individual
command. To update any given display, you must reissue the previous
command. When using SDA to analyze a running system, you should
thus use caution in interpreting its displays. Because system states change
frequently, it is possible that the information SDA displays may be
inconsistent with the actual, volatile state of the system at any moment.

•

Certain SDA commands are illegal in this mode, such as SHOW CPU and
SET CPU. Use of these commands results in the error message
%SDA-E-CMDNOTVLD, command not valid on the running system

•

The SHOW CRASH command, although valid, does not display the
contents of any of the processor's set of hardware registers. Also, the
"Time of system crash" information refers to the time at which the
ANALYZE/SYSTEM command was given.

SDA Context
When invoked to analyze either a crash dump or a running system, SDA
establishes a default context for itself from which it interprets certain
commands.
When the subject of analysis is a VMS uniprocessor system, SDA's context
is solely process context. That is, SDA can interpret its process-specific
commands in the context of either the process current on the uniprocessor
or some other process in some other scheduling state. When you initially
invoke SDA to analyze a crash dump, its process context defaults to that of
the process that was current at the time of the crash. When you invoke SDA
to analyze a running system, its process context defaults to that of the current
process; that is, the one executing SDA. You can change SDA's process
context by issuing any of the following commands:
SET PROCESS /INDEX=nn
SET PROCESS name
SHOW PROCESS /INDEX=nn

SDA-9

SDA Description

When you invoke SDA to analyze a crash dump from a VMS multiprocessing
system with more than one active CPU, SDA maintains a second dimension
of context-its CPU context-that allows it to display certain processorspecific information, such as the reason for the bugcheck exception, the
currently executing process, the current IPL, the contents of processor-specific
registers, the interrupt stack pointer (ISP), and the spin locks owned by the
processor. When you invoke SDA to analyze a multiprocessor's crash dump,
its CPU context defaults to that of the processor that induced the system
failure. 3
You can change the SDA CPU context by using any of the following
commands:
SET CPU cpu-id
SHOW CPU cpu-id
SHOW CRASH
Changing CPU context involves an implicit change in process context in
either of the following ways:
•

If there is a current process on the CPU made current, SDA process

context is changed to that of that CPU's current process.
•

If there is no current process on the CPU made current, SDA process

context is undefined and no process-specific information is available until
SDA process context is set to that of a specific process.
Likewise, changing process context can involve a switch of CPU context as
well. For instance, if you issue a SET PROCESS command for a process that
is current on another CPU, SDA will automatically change its CPU context to
that of the CPU on which that process is current. The following commands
can have this effect if the name or index number (nn) refers to a current
process.
SET PROCESS name
SET PROCESS /INDEX=nn
SHOW PROCESS name
SHOW PROCESS /INDEX=nn

SDA Command Format
The following sections describe the format of SDA commands and the
expressions you can use with SDA commands.

When you are analyzing a running system, CPU context is not accessible to SDA. Therefore, the SET CPU and
SHOW CPU commands are not permitted.

SDA-10

SDA Description

5.1

General Command Format
SDA uses a command format similar to that used by the DCL interpreter.
You issue commands in this general format:
command-name[/qualifier ... ] [parameter][/qualifier ... ] [!comment]

The command-name is an SDA command. Each command tells the utility to
perform a function. Commands can consist of one or more words, and can be
abbreviated to the number of characters that make the command unique. For
example, SH stands for SHOW, and SE stands for SET.
The parameter is the target of the command. For example, SHOW PROCESS
RUSKIN tells SDA to display the context of the process RUSKIN. The
command EXAMINE 80104CD0;40 displays the contents of 40 bytes of
memory, beginning with location 80104CDO.
When you supply part of a file specification as a parameter, SDA assumes
the following default values for the omitted portions of the specification.
The default device is SYS$DISK, the device specified in your most recent SET
DEFAULT command. Likewise, the default directory is the directory specified
in the most recent SET DEFAULT command. See the VMS DCL Dictionary for
a description of the DCL command SET DEFAULT.
The qualifier modifies the action of an SDA command. A qualifier is always
preceded by a slash ( / ). Several qualifiers can follow a single parameter or
command name, but each must be preceded by a slash. Qualifiers can be
abbreviated to the shortest string of characters that uniquely identifies the
qualifier.
The comment consists of text that describes the command, but is not actually
part of the command. Comments are useful for documenting SDA command
procedures. When executing a command, SDA ignores the exclamation point
and all characters that follow it on the same line.

5.2

Expressions
You can use expressions as parameters for some SDA commands, such as
SEARCH and EXAMINE. To create expressions, you can use any of the
following elements:
•

Numerals

•

Radix operators

•

Arithmetic and logical operators

•

Precedence operators

•

Symbols

As mentioned, numerals are one possible component of an expression. The
following sections describe the use of the other components.

SDA-11

SDA Description

5.2.1

Radix Operators

Radix operators determine which numeric base SDA uses to evaluate
expressions. You can use one of the three radix operators to specify the
radix of the numeric expression that follows the operator:
•

AX (hexadecimal)

•

AO (octal)

•

AD (decimal)

The default radix is hexadecimal. SDA displays hexadecimal numbers with
leading zeros and decimal numbers with leading spaces.
5.2.2

Arithmetic and Logical Operators
There are two types of arithmetic and logical operators, both of which are
listed in Table SDA-2.

•

Unary operators affect the value of the expression that follows them.

•

Binary operators combine the operands that precede and follow them.

In evaluating expressions containing binary operators, SDA performs logical
AND, OR, and XOR operations, and multiplication, division, and arithmetic
shifting before addition and subtraction. Note that the SDA arithmetic
operators perform integer arithmetic on 32-bit operands.
Table SDA-2
Operator

SDA Operators

Action

Unary Operators
#

Performs a logical NOT of the expression

Makes the value of the expression positive
Makes the value of the expression negative

Evaluates the following expression as a virtual address, then uses
the contents of that address as value

Adds 80000000 16 to the value of the expression 1

Adds 7FFE0000 16 to the value of the expression 2

Binary Operators
+

Addition
Subtraction
Multiplication

Logical AND
Logical OR

1 The unary operator G corresponds to the first virtual address in system space. For
example, the expression GD40 can be used to represent the address 80000040 16 .
2 The unary operator H corresponds to a convenient base address in the control region of
a process (7FFE0000 16 ). You can therefore refer to an address such as 7FFE2A64 16 as
H2A64.

SDA-12

SDA Description

Table SDA-2 (Cont.}
Operator

SDA Operators

Action

Binary Operators

Logical XOR

Division 3

Arithmetic shifting

3 1n division, SDA truncates the quotient to an integer, if necessary, and does not retain a

remainder.

5.2.3

Precedence Operators
SDA uses parentheses as precedence operators. Expressions enclosed
in parentheses are evaluated first. SDA evaluates nested parenthetical
expressions from the innermost to the outermost pairs of parentheses.

5.2.4

Symbols
Names of symbols can contain from 1 to 31 alphanumeric characters and can
include the dollar sign ( $) and underscore (-) characters. Symbols can take
values from -7FFFFFFF 16 to 7FFFFFFF 16 .

By default, SDA copies symbols into its symbol table from
SYS$SYSTEM:SYS.STB and SYS$SYSTEM:REQSYSDEF.STB. Additional
symbols can be taken from other symbol tables or object modules and added
to the SDA symbol table with the READ command. You can also use the
DEFINE command to create symbols and add them to the symbol table.
In addition, SDA provides the symbols described in Table SDA-3:
Table SDA-3

SDA Symbols

Symbol

Meaning

. (period)

Current location

Argument pointer 1

CLUSTRLOA

Base address of loadable V AXcluster code

nnDRIVER

Base address of a driver prologue table
(DPT); such a symbol exists for each loaded
device driver in the system 2

ESP

Executive stack pointer 1

Frame pointer 1

FPEMUL

Base address of the code that emulates
floating-point instructions

The value of those symbols representing the current SDA process context changes
whenever you issue a command that changes this context (see Section 4). These symbols
include the general purpose registers (RO through R11, AP, FP, PC, and SP); the perprocess
stack pointers (USP, SSP, KSP); the page table base and length registers (POBR, POLR,
P 1BR, and P 1LR); and the processor status longword (PSL).
2 The notation

nn within the symbol nn DRIVER represents a 2-letter, generic device
/controller name (for example, LPDRIVER).

SDA-13

SDA Description

Table SDA-3 (Cont.)

SDA Symbols

Symbol

Meaning

80000000 16 , the base address of system
space

7FFE000015

KSP

Kernel stack pointer 1

MCHK

Address within loadable CPU-specific
routines

MSCP

Address of loadable MSCP server code

POBR

Base register for the program region (PO) 1

POLR

Length register for the program region (PO) 1

P1BR

Base register for the control region (P 1) 1

P1LR

Length register for the control region (P 1) 1

Program counter 1

PSL

Processor status longword 1

RO through R 11

General registers 1

RMS

Base address of the RMS image

SCSLOA

Base address of loadable common SCS
services

Current stack pointer of a process 1

SSP

Supervisor stack pointer 1

SYSLOA

Base address of loadable processor-specific
system code

USP

User stack pointer 1

1The value of those symbols representing the current SDA process context changes
whenever you issue a command that changes this context (see Section 4). These symbols
include the general purpose registers (RO through R11, AP, FP, PC, and SP); the perprocess
stack pointers (USP, SSP, KSP); the page table base and length registers (POBR, POLR,
P1BR, and P1LR); and the processor status longword (PSL).

When SDA displays an address, it displays that address both in hexadecimal
and as a symbol, if possible. If the address is within FFF 16 of the value
of a symbol, SDA displays the symbol plus the offset from the value of that
symbol to the address. If more than one symbol's value is within FFF 16 of the
address, SDA displays the symbol whose value is the closest. If no symbols
have values within FFF 16 of the address, SDA displays no symbol. (For an
example, see the description of the SHOW STACK command.)

SDA-14

SDA Description

Investigating System Failures
This section discusses how the VMS operating system handles internal errors,
and suggests procedures that can aid you in determining the causes of these
errors. To conclude, it illustrates, through detailed analysis of a sample
system failure, how SDA helps you find the causes of operating system
problems.
For a complete description of the commands discussed in the sections that
follow, refer to the last part of this document, where all the SDA commands
are discussed in alphabetical order.

6.1

General Procedure for Analyzing System Failures
When the VMS operating system detects an internal error so severe that
normal operation cannot continue, it signals a condition known as a fatal
bugcheck and shuts itself down. A specific bugcheck code describes each
such error.
To resolve the problem, you must find the reason for the bugcheck. Most
failures are caused by errors in user-written device drivers or other privileged
code not supplied by DIGITAL. To identify and correct these errors, you need
a listing of the code in question.
Occasionally a system failure is the result of a hardware failure or an error
in code supplied by DIGITAL. A hardware failure requires the attention
of DIGITAL Field Service. To diagnose an error in code supplied by
DIGITAL, you need listings of that code, which is available from DIGITAL on
microfiche.
Start the search for the error by locating the line of code that signaled the
bugcheck. Invoke SDA and use the SHOW CRASH command to display the
content of the program counter (PC). The content of the PC is the address of
the next instruction after the instruction that signaled the bugcheck.
The PC often contains an address in the exception handler, which signaled
the bugcheck but did not cause it. In this case, the address of the instruction
that caused the bugcheck is located on the stack. Use the SHOW STACK
command to display the contents of the stack. See Section 6.2 for information
on how to proceed for several types of bugchecks.
Once you have found the address of the instruction that caused the bugcheck,
you need to find the module in which the failing instruction resides. Use the
SHOW DEVICE command to determine whether the instruction is part of a
device driver.
If it is not part of a driver, examine the linker's map of the module or
modules you are debugging to determine whether the instruction that caused
the bugcheck is in your programs.
If it is not within a driver or other code not supplied by DIGITAL, perform
the following steps:

Issue the SDA command
SDA> SHOW EXECUTIVE

This command shows the location and size of each of the loadable images
that make up the VMS executive.

SDA-15

SDA Description

Compare the suspected address with the addresses of these system
images.

If the address is in fact within one of these images, issue the command
SDA> READ/EXECUTIVE

SYS$LOADABLE_IMAGES:

This command loads the symbols that define locations within the loadable
portion of the VMS executive.
4

Examine the failing address by issuing the command
SDA> EXAMINE ©PC

SDA then displays the address in the PC as an offset from the nearest
global symbol. This symbol may be the module's starting address,
although it is possible that the code you are examining may not be in the
module whose name is displayed.
Now, to determine the general cause of the system failure, examine the code
that signaled the bugcheck.

6.2

Fatal Bugcheck Conditions
There are several conditions that cause VMS to issue a bugcheck. Normally,
these occasions are rare. When they do occur, it is likely that they are in the
nature of a fatal exception or an illegal page fault occurring within privileged
code. This section describes the symptoms of these bugchecks. A discussion
of other exceptions and VMS condition handling in general appears in the

VMS System Services Volume.
6.2.1

Fatal Exceptions

An exception is fatal when it occurs while the following conditions exist:
•

The process is using the interrupt stack.

•

The process is executing above IPL 2 (IPL$_ASTDEL).

•

The process is executing in a privileged (kernel or executive) processor
access mode and has not declared a condition handler to deal with the
exception.

When the system fails, VMS reports the approximate cause of the failure
on the console terminal. SDA displays a similar message when you issue
a SHOW CRASH command. For instance, for a fatal exception, SDA can
display one of these messages:
FATALEXCPT, Fatal executive or kernel mode exception
INVEXCEPTN, Exception while above ASTDEL or on interrupt stack
SSRVEXCEPT, Unexpected system service exception

Although there are several possible exception conditions, access violations are
most common. When the hardware detects an access violation, information
useful in finding the cause of the violation is pushed onto either the kernel
stack or the interrupt stack. If the access violation occurred when it was using
the interrupt stack, VMS places this information on the interrupt stack.
The INVEXCEPTN and SSRVEXCEPT bugchecks place three argument lists,
or arrays, on the stack:
SDA-16

SDA Description

The first argument list appears near the top of the stack (see Figure SDA-1)
and contains the number 2 in its first longword, indicating that the following
two longwords complete the array. 4 These two longwords contain the
addresses on the stack of the signal array and mechanism array.
Figure SDA-1

First Argument List on the Stack

00000002
signal array address
mechanism array address
ZK-1920-84

The mechanism array (see Figure SDA-2) appears lower on the stack, at the
address specified in the first argument list. Its first longword contains a 4,
indicating that the four subsequent longwords complete the array. These
four longwords are used by the VMS procedures that search for a condition
handler and report exceptions.
Figure SDA-2

Mechanism Array

00000004
frame
depth

RO
R1

ZK-1921-84

This array sometimes does not appear on the stack. The mechanism and signal arrays, however, may still be
present.

SDA-17

SDA Description

The values contained in the mechanism array are defined as follows:
Value

Meaning

00000004

Number of longwords that follow. In a mechanism array, this value
is always 4.

Frame

Address of the FP (frame pointer) of the establisher's call frame.

Depth

Depth of the VMS search for a condition handler.

Contents of RO at the time of the exception.

Contents of R 1 at the time of the exception.

The signal array (see Figure SDA-3) appears somewhat further down the
stack, at the address specified in the first argument list. A signal array
contains the exception code, zero or more exception parameters, the PC, and
the PSL. The size of a signal array can thus vary from exception to exception.
Figure SDA-3

Signal Array

00000005

oooooooc
reason mask
virtual address
PC
PSL
ZK-1922-84

SDA-18

SDA Description

For access violations, the signal array is set up as follows:
Value

Meaning

00000005

Number of longwords that follow. For access violations,
this value is always 5.

oooooooc

Exception code. The value OC 16 represents an access
violation. You can identify the exception code by using
the SDA command EVALUATE/CONDITION.

Reason mask

Longword mask. If bit 0 of this longword is set, the
failing instruction (at the PC saved below) caused a length
violation. If bit 1 is set, it referred to a location whose
page table entry is in a "no access" page. Bit 2 indicates
the type of access used by the failing instruction: it is
set for write and modify operations and clear for read
operations.

Virtual address

Virtual address that the failing instruction tried to
reference.

PC whose execution resulted in the exception.

PSL

PSL at the time of the exception.

If VMS encounters a fatal exception, you can find the code that signaled it by

examining the PC in the signal array. Use the SHOW STACK command to
display the stack in use when the failure occurred, then locate the mechanism
and signal arrays. Once you obtain the PC, which points to the instruction
that signaled the exception, you can identify the module where the instruction
is located by following the instructions in Section 7.3.

6.2.2

Illegal Page Faults
VMS signals a PGFIPLHI bugcheck when a page fault occurs while the
interrupt priority level (IPL) is greater than 2 (IPL$_ASTDEL). When VMS
fails because of an illegal page fault, it prints the following message on the
console terminal:
PGFIPLHI, Page fault with IPL too high

SDA-19

SDA Description

When an illegal page fault occurs, the stack appears as pictured in
Figure SDA-4. Six longwords describe the exception:
Longword

Contents

Contents of R4 at the time of the bugcheck.

Contents of R5 at the time of the bugcheck.

Reason mask

Longword mask. If bit 0 of this longword is set, the
failing instruction (at the PC saved below) caused a length
violation. If bit 1 is set, it referred to a location whose
page table entry is in an "access" page. Bit 2 indicates
the type of access used by the failing instruction: it is
set for write and modify operations and clear for read
operations.

Virtual address

Virtual address being referenced by the instruction that
caused the page fault.

PC containing the address of the instruction that caused
the page fault.

PSL

PSL at the time of the page fault.

Figure SDA-4

Stack Following an Illegal Page-Fault Error

R4
R5

reason mask
virtual address
PC
PSL
ZK-1923-84

If the operating system detects a page fault while the IPL is higher than
IPL$_ASTDEL, you can obtain the address of the instruction that caused the
fault by examining the PC pushed onto the current operating stack. Follow
the steps outlined in Section 7.3 to determine which module issued the
instruction.

SDA-20

SDA Description

A Sample System Failure
This section steps through the analysis of a system failure using, as an
example, a printer driver. Three events lead up to this failure:
1

The line printer goes off line for three hours.

The line printer comes back on line.

The VMS operating system signals a bugcheck, writes information to the
system dump file, and shuts itself down.

The following sections describe the actions you should take when
investigating the causes of this system crash.

7. 1

Identifying the Bugcheck
First, invoke SDA to analyze the system dump file. The initialization message
indicates the type of bugcheck that occurred as follows:
VAX/VMS System dump analyzer
Dump taken on 31-JAN-1989 16:34:31.23
INVEXCEPTN, Exception while above ASTDEL or on interrupt stack
SDA>

VMS encountered an exception that caused it to signal a bugcheck, and it has
created the signal and mechanism arrays on the current operating stack.

7 .2

Identifying the Exception
Use the SHOW STACK command to display the current operating stack.
In this case, it is the interrupt stack. The following example shows the
interrupt stack and the signal and mechanism arrays. See the description of
the SHOW STACK command for a complete description of the format of the
stack display.

SDA-21

SDA Description

CPU 01 Processor stack
Current operating stack (INTERRUPT)
8006A378

8000844B

SP => 8006A398
8006A39C
8006A3AO
8006A3A4
8006A3A8
8006A3AC
8006A3BO
8006A3B4
8006A3B8
8006A3BC
8006A3CO
8006A3C4
8006A3C8
8006A3CC
8006A3DO
8006A3D4
8006A3D8

7FFDC340
8006A3AO
80004E7D
04080009
00000004
7FFDC368
FFFFFFFD
8001774E
0000074F
00000001
00000005

ACP$WRITEBLK+OAO

EXE$REFLECT+OD4

oooooooc

00000000
80069EOO
8005D003
04080000
80009604

EXE$FORKDSPTH+01C

The mechanism array begins at address 8006A3A8 16 and ends at address
8006A3B8 16 . Its first longword contains 00000004 16 . The signal array begins
at address 8006A3C0 16 and ends at 8006A3D4 16 . Its first longword contains
00000005 16 and its second longword contains OOOOOOOC 16 . Examination of
the signal array shows that
•

The exception code is OC 16 , indicating an access violation.

•

The reason mask is zero, indicating that the instruction caused a
protection violation (instead of a length violation) when it tried to read
the location (rather than write to it).

•

The virtual address that the instruction attempted to reference was
80069E0016·

•

The PC of the instruction that referred to the bad virtual address was
8005D00316·

Issuing the SDA command EVALUATE/PSL 04080000 makes the following
information apparent:

SDA-22

•

The IPL was 8 at the time of the exception (shown by bits 16 through 20
of the PSL).

•

The current operating stack was the interrupt stack (bit 26 of the PSL is
set to 1).

•

The process was executing in kernel mode at the time of the exception
(shown by bits 24 and 25 of the PSL).

SDA Description

Use the SHOW PAGE_TABLE command to display the system page table, as
shown in the example following. The page containing location 80069E00 16 is
not available to any access mode (a null page); thus the virtual address is not
valid.
SDA> SHOW PAGE_TABLE
System page table

ADDRESS

SVAPTE

PTE

80068400 80777B08 7C40FFC8
80068600 80777BOC 7C40FFC8
80068800 80777B10 7C40FFC8
80068AOO 80777B14 7C40FFC8
80068COO 80777B18 7C40FFC8
80068EOO 80777B1C 7C40FFC8
80069000 80777B20 7C40FFC8
80069200 80777B24 7C40FFC8
80069400 80777B28 7C40FFC8
80069600 80777B2C 7C40FFC8
80069800 80777B30 7C40FFC8
80069AOO 80777B34 780016C9
80069COO 80777B38 78000E15
-------- 40 NULL PAGES

7 .3

TYPE PROT

STX UR
STX UR
STX UR
STX UR
STX UR
STX UR
STX UR
STX UR
STX UR
STX UR
STX UR
TRANS UR
TRANS UR

BITS PAGTYP

LDC STATE TYPE REFCNT

K
K
K
K
K
K
K
K
K
K
K
K SYSTEM FREELST 00
K SYSTEM FREELST 00

01
01

0
0

BAK

0040FFC8
0040FFC8

SVAPTE

FLINK

BLINK

80777B34 03AF
80777B38 16C9

OE15
2592

Locating the Source of the Exception
Because the printer went off line and then came back on line, as shown on
the console listing, the problem might exist in the driver code. SDA can help
you to determine which driver might contain the faulty code.

7.3.1

Finding the Driver by Using the Program Counter
The first step in determining whether the failing instruction is within a driver
is to examine the PC in the signal array using the EXAMINE/INSTRUCTION
command. This has two results:
1

It displays, if possible, the contents of the address as a VAX MACRO
instruction.

It identifies the address as an offset from the symbol, nnDRIVER, if the
address lies within the first FFF 16 bytes of such a symbol. SDA defines
a symbol in the form of nnDRIVER for each device driver connected
to the system. This symbol represents the base of the driver prologue
table (DPT). Each DPT is part of the device driver it describes and is
immediately followed by that driver's code.

In the following example, the instruction that caused the exception is located
within the printer driver.
SDA> EXAMINE/INSTRUCTION 80050003
LPDRIVER+2B3
MOVB
(R3)+,(RO)

If SDA is unable to find a symbol within FFF 16 bytes of the memory location
you specify, it displays the location as an absolute address. This often, but
not always, means the instruction that caused the exception is not part of a
device driver.

SDA-23

SDA Description

To determine whether an instruction is or is not part of a driver, use the
SHOW DEVICE command to display the starting addresses and lengths of all
the drivers in the system. If the address of the failing instruction falls within
the range of addresses shown for a given driver, the failing instruction is a
part of that driver. The following example shows a partial list of the drivers
in the display generated by the SHOW DEVICE command.
I/O data structures
DDB list
--------

7.3.2

Address
-------

Controller

80000ECC
80001040
8000126C
80001460
801E2800
801E2980

HELIUM$DBA
OPA
MBA
NLA
HELIUM$DMA
HELIUM$DLA

ACP

Driver

DPT

F11XQP

DBDRIVER
OPERATOR
MBDRIVER
NLDRIVER
DMD RIVER
DLDRIVER

800F7ADO
80001622
80001580
800015E9
800B5CBO
800B6A50

----------

F11XQP
F11XQP

DPT size
-------08FD
0061
0578
05A3
OAAO
0800

Calculating the Offset into the Driver's Program Section
The offsets that SDA displays from nnDRIVER are actually offsets from the
DPT. As such, these offsets do not exactly correspond to the offsets shown
in driver listings, which represent offsets from the beginning of the program
section (PSECT) in which a given instruction appears. Because a driver
usually contains more than one PSECT, you must use the driver's map to
determine the location of the failing instruction within the driver listing.

To calculate the location of the instruction within the driver listing, refer to
the "Program Section Synopsis" section of the driver's map. Determine in
which PSECT the offset given by SDA occurs and subtract the base of the
PSECT from the offset. You can then use the resulting figure as an index into
the driver listing.
If SDA does not display the address as an offset from nnDRIVER, but the
address is within the address range of a driver in the SHOW DEVICE display,
you must first subtract the address of the DPT from the failing address. Using
the result as the offset, you can then follow the steps previously outlined for
determining the index of the instruction into a driver listing.

7 .4

Finding the Problem Within the Routine
To find the problem within the routine, examine the printer's driver code.
In the system failure discussed in this example, the instruction that caused
the exception is MOVB (R3)+,(RO). To check the contents of R3, use the
EXAMINE command as follows:
SDA> EXAMINE R3
R3 : 80069EOO II . • . • II

The invalid virtual address, as recorded in the signal array, is stored in R3.
In the following driver code excerpt, the instruction in question appears at
line 599. It is likely that the contents of R3 have been incremented too many
times.

SDA-24

SDA Description

581 STARTIO:
582
MOVL
UCB$L_IRP(R5),R3
;Retrieve address of I/O packet
IRP$L_MEDIA+2(R3) .583
MOVW
584
UCB$W_BOFF(R5)
;Set number of characters to print
585
MOVL
UCB$L_SVAPTE(R5),R3 ;Get address of system buffer
586
MOVAB
12(R3),R3
;Get address of data area
MOVL
UCB$L_CRB(R5),R4
;Get address of CRB
587
588
MOVL
©CRB$L_INTD+VEC$L_IDB(R4),R4 ;Get device CSR address
589
590
START NEXT OUTPUT SEQUENCE
591
592
593 10$: ADDL3
#LP_DBR,R4,RO
;Calculate address of data buffer register
594
MOVZWL UCB$W_BOFF(R5),R1
;Get number of characters remaining
MOVW
#-X8080,R2
;Get control register test mask
595
596
BRB
25$
;Start output
597 20$: BITW
R2,(R4).,
;Printer ready or have paper problem?
598
BLEQ
30$
;If LEQ not ready or paper problem
599
MOVB
(R3)+,(RO)f)
;Output next character
ASHL
#1,G-EXE$GL_UBDELAY,-(SP)
;Delay 3*2 u-seconds
600
601 24$: SOBGEQ (SP),24$
;Delay loop calibrated to machine speed
ADDL
#4,SP
;Pop extra longword off stack
602
603 25$: SOBGEQ R1,20$8
;Any more characters to output?
BRW
70$
;All done, BRW to set return status
604

7.4.1

Examining the Routine
The MOVB instruction is part of a routine that reads characters from a buffer
and writes them to the printer. The routine contains the loop of instructions
that starts at the label 20$ and ends at 25$. This loop executes once for each
character in the buffer, performing these five steps:

., The driver checks the printer's status register to see if the printer is ready.
f)

If the printer is ready, the driver gets a character from the buffer and
moves it to the printer's data register, to which RO points

It then decrements Rl, which contains the count of characters left to print.
If Rl contains a number greater than zero, control is passed back to the
instruction at 20$, and the loop begins again.

Steps 1 and 2 are repeated until the contents of Rl are 0 or the printer signals
that it is not ready.
If the printer signals that it is not ready, the driver transfers control to
30$ (line 598), the beginning of a routine that waits for an interrupt from
the printer. When the printer becomes ready, it interrupts the driver, and
execution of the loop resumes.

Examine the code to determine which variables control the loop.
The byte count (BCNT) is the number of characters in the buffer. Note that
BCNT is set by a function decision table (FDT) routine and that this routine
sets the value of BCNT to the number of characters in the buffer. In line 586,
the starting address of a buffer that is BCNT bytes in size is moved into R3.
Note also that the number of characters left to be printed is represented by
the byte offset (BOFF), the offset into the buffer at which the driver finds the
next character to be printed. This value controls the number of times the loop
is executed.

SDA-25

SDA Description

Because the exception is an access violation, either R3 or RO must contain an
incorrect value. You can determine that RO is probably valid by the following
logic:
•

The instruction at 10$ (ADDL3 #LP_DBR,R4,RO) places an address in RO
and RO is not modified again until the failing instruction (line S99).

•

The value in R4 at the time that the instruction at 10$ is executed was
derived from the addresses of the device's unit control block (UCB) (line
S87) and CRB (line S99). Although it is possible that these data structures
may contain wrong information, it is unlikely.

Thus, the contents of R3 seem to be the cause of the failure.
The most likely reason that the contents of R3 are wrong is that the MOVB
instruction at line S99 executes too many times. You can check this by
comparing the contents of UCB$W_BOFF and UCB$W_BCNT. If UCB$W_
BOFF contains a larger value than that in UCB$W_BCNT, then R3 contains a
value that is too large, indicating that the MOVB instruction has incremented
the contents of R3 too many times.

7.4.2

Checking the Values of Key Variables
Because the start-1/0 routine requires that RS contain the address of the
printer's UCB, and because several other instructions reference RS without
error before any instruction in the loop does, you can assume that RS contains
the address of the right UCB. To compare BOFF and BCNT, use the command
FORMAT @RS to display the contents of the UCB, as shown in the following
session:
SDA> READ SYS$SYSTEM:SYSDEF.STB
SDA> FORMAT @R5
80050160

80050164
80050168
8005D16A
8005D16B

8005D1C8
8005D1CC
8005D1CE
8005D1DO
8005D1D1
8005D1D2

UCB$L_FQFL
800039A8
UCB$L_RQFL
UCB$W_MB_SEED
UCB$W_UNIT_SEED
UCB$L_FQBL
800039A8
UCB$L_RQBL
UCB$W_SIZE
0122
UCB$B_TYPE
10
UCB$B_FIPL
34
UCB$B_FLCK

UCB$L_SVAPTE
UCB$W_BOFF
UCB$W_BCNT
UCB$B_ERTCNT
UCB$B_ERTMAX
UCB$W_ERRCNT

80062720
0795
006D
00
00
0000

SDA>

If you have only one printer in your system configuration, you need not use

the FORMAT command. Instead, you can use the command SHOW
DEVICE LP. Because only one printer is connected to the VAX processor, only
one UCB is associated with a printer for SDA to display.

SDA-26

SDA Description

The output produced by the FORMAT @RS command shows that UCB$W_
BOFF contains a value greater than that in UCB$W_BCNT; it should be
smaller. Therefore, the value stored in BOFF is incorrect.
Thus, the value of BOFF is not the number of characters that remain in the
buffer. This value is used in calculating an address that is referenced at an
elevated IPL. When this address is within a null page (unreadable in all access
modes), an attempt to reference it causes the system to fail.

7.4.3

Identifying and Fixing the Defective Code
Examine the printer driver code to locate all instructions that modify UCB$W_
BOFF. The value changes in two circumstances:

•

Immediately after the driver detects that the printer is not ready and that
the problem is not a paper problem (line 609).

•

When the wait-for-interrupt routine's timeout count of 12 seconds is
exhausted (lines 616 and 630). At this time, the contents of Rl, plus one,
are stored in UCB$W_BOFF (line 631).

When the printer times out, the driver should not modify UCB$W_BOFF.
It does so, however, in line 631. The driver should modify the contents of
UCB$W_BOFF only when it is certain that the printer printed the character.

When the printer times out, this is not the case. Furthermore, the waitfor-interrupt routine preserves only registers R3, R4, and RS, so only these
registers can be used unmodified after the execution of the wait-for-interrupt
routine. Thus the use of Rl in line 631 is an error.
To correct the problem, change the WFIKPCH argument (line 616) so that,
when the printer times out, the WFIKPCH macro transfers control to SO$
rather than to 40$.
607
40$
;If NEQ paper problem
608 30$: BNEQ
ADDW3
#1,R1,UCB$W_BOFF(R5) ;Save number of characters remaining
609
DEVICELOCK 610
LOCKADDR=UCB$L_DLCK(R5) ,- ;Lock device interrupts
611
612
SAVIPL=-(SP)
;Save current IPL
BITW
#AX80,LP_CSR(R4)
;Is it ready now?
613
614
BNEQ
35$
;If NEQ, yes, it's ready
BISB
#AX40,LP_CSR(R4)
;Set interrupt enable
615
616
WFIKPCH 40$,#12
;Wait for ready interrupt
617
IOFORK
;Create a fork process
BRB
10$
... and start next output
618
619
620 35$:
621
DEVICEUNLOCK LOCKADDR=UCB$L_DLCK(R5) ,- ;Unlock device interrupts
622
NEWIPL=(SP)+
;Restore IPL
623
624
CLRW
LP_CSR(R4)
;Disable device interrupts
625
BRB
10$
;Go transfer more characters

SDA-27

SDA Description

626
627
PRINTER HAS PAPER PROBLEM
628
629
630 40$: CLRL
UCB$L_LP_OFLCNT(R5) ;Clear offline counter
631
ADDW3
#1,R1,UCB$W_BOFF(R5) ;Save number of characters remaining
632 50$: CLRW
LP_CSR(R4)
;Disable printer interrupt
633
IOFORK
;Lower to fork level
634
BBS
#UCB$V_CANCEL,UCB$W_STS(R5) ,80$ ;If set, cancel I/O operation
635
TSTW
LP_CSR(R4)
;Printer still have paper problem?
636
BLSS
55$
;If LSS yes
637
MOVL
#15,UCB$L_LP_TIMEOUT(R5) ;Set timeout value
638
BRB
10$
; ... and start next output

Inducing a System Failure
If the operating system is not performing well and you want to create a
dump you can examine, you must induce a system failure. Occasionally a
device driver or other user-written, kernel-mode code can cause the system
to execute a loop of code at a high priority, interfering with normal system
operation. This can occur even though you have set a breakpoint in the
code if the loop is encountered before the breakpoint. To gain control of the
system in such circumstances, you must cause the system to fail and then
reboot it.
If the system has suspended all noticeable activity (if it is "hung"), see the
examples of causing system failures at the end of this section.
If you are generating a system crash in response to a system hang, be sure
to record the PC at the time of the system halt as well as the contents of
the general registers. Submit this information to DIGITAL, along with the
Software Performance Report (SPR), and a copy of the generated system
dump file.

8.1

Meeting Crash Dump Requirements
The following requirements must be met before the VMS system can write a
complete crash dump:
1

You must not halt the system until the console dump messages have been
printed in their entirety and the memory contents have been written to
the crash dump file. Be sure to allow sufficient time for these events to
take place or make sure that all disk activity has stopped before using the
console to halt the system.

There must be a crash dump file in SYS$SYSTEM: named either
SYSDUMP.DMP or PAGEFILE.SYS.
This dump file must be either large enough to hold the entire contents
of memory (as discussed in Section 1.1) or, if the DUMPSTYLE system
parameter is set, large enough to accommodate a subset dump (see
Section 1.1.1 ).
If SYSDUMP.DMP is not present, VMS attempts to write crash dumps to
PAGEFILE.SYS. In this case, the SAVEDUMP system parameter must be
1 (the default is 0).

SDA-28

The system DUMPBUG parameter must be 1 (the default is 1).

SDA Description

8.2

Examples of How to Cause System Failures
The following examples show the sequence of console commands needed to
cause a system failure on each type of VAX processor. In each instance, after
halting the processor and examining its registers, you place the equivalent of
-1 (for example FFFFFFFF 16 ) into the PC. The value placed in the PSL sets
the processor access mode to kernel and the IPL to 31. After these commands
are executed, an INVEXCEPTN bugcheck is reported on the console terminal,
followed by a listing of the contents of the processor registers.
The console volume of most processors contains a command file named
either CRASH.COM or CRASH.CMD that you can execute to perform these
commands. Note that the console sessions recorded in this section omit much
of the information the console displays in response to the listed commands.
VAX 8530/8550/8700/8800/8830/8850

The following series of console commands causes a system failure on the VAX
8530 /8550 /8700 /8800 /8830 /8850 systems. (Note that the console prompt
for the VAX 8830 and 8850 systems is PS-CI0-0> and not > > > .)
$ lcTRL/Pl
>>> SET CPU CURRENT_PRIMARY

»> HALT
?00

Left CPU -- CPU halted
PC = 8001911C

»> ©CRASH
! Command procedure to force VMS bugcheck via access violation
!

SET VERIFY
SET CPU CURRENT_PRIMARY
!Select primary
EXAMINE PSL
!Display PSL
M 00000000 00420008
EXAMINE/I/NEXT 4 0

DEPOSIT PC FFFFFFFF
DEPOSIT PSL 41FOOOO
CONTINUE

!Set PC=-1 to force ACCVIO
!Set IPL=31, interrupt stack
!Execute from PC=-1

VAX 8200/8250/8300/8350 and VAX 6200 Series

The following console commands cause a system failure on a VAX 8200/8250
/8300 /8350 system or a VAX 6200 series system. In these systems, the HALT
command is a NOP; a CTRL/P automatically halts the processor.
$ lcTRL/Pl

PC = 80008B1F
>>> E p
»> E/I 0

»> E/I +
»> E/I +
»> E/I +
»> E/I +
>>> D/G F FFFFFFFF
»> D P 41FOOOO
>>> c

SDA-29

SDA Description

VAX 8600/8650/8670
The following console commands cause a system failure on the VAX 8600
/8650 /8670 systems.
$ icTRL/Pj

>» ©CRASH

SET QUIET OFF
!Make clearer
SET ABORT OFF
!Don't abort on E/VIR command
HALT
CPU stopped, INVOKED BY CONSOLE (CSM code 11)
PC 80008B1F
UNJAM
!Clear the way
E PSL
!Display PSL
U PSL 00000000
E/I/N:4 0
!Display stack pointers

E SP

!Get current stack pointers

G OE 80000C40
E/vir/next:40 ©

!Dump top of stack

D PC FFFFFFFF
D PSL 1FOOOO
SET ABORT ON
SET QUIET ON
CONTINUE

!Invalidate the PC
!Kernel mode, IPL 31
!Restore abort flag
!Shut output off
!Force a machine check

VAX-11/780 and VAX-11/785
The following console commands cause a system failure on the VAX-11 /780
and VAX-11/785 processors.
$ !cTRL/PI

>» @CRASH
HALT
HALTED AT 80008A89

EXAMINE PSL
00000000

!PSL,

EXAMINE/INTERN/NEXT:4 0

!and all stack pointers

DEPOSIT PC = -1
DEPOSIT PSL = 1FOOOO

!Invalidate PC
!Kernel mode, IPL 31

CONTINUE

SDA-30

!Halt system, examine PC,

SDA Description

VAX-11/750

The following code causes a system failure on a VAX-11/750. On a VAX-11
/750 processor, the HALT command is a NOP; a CTRL/P automatically halts
the processor.
$ lCTRL/Pl
>>> H

»> E p
»> E/I 0
»> E/I +
>» E/I +
»> E/I +
>» E/I +
>>> D/G F FFFFFFFF
»> D P 1FOOOO
>>> c

MicroVAX 3600 Series, MicroVAX II, and MicroVAX I

To force a crash of a MicroVAX, you must first halt the processor. (Once the
processor is halted, press the HALT button again so that it is popped out and
is not illuminated.) Then, issue the following console commands:
>>> E PSL
>>> E/I/N :4 0
>>> D PC FFFFFFFF
>>> D PSL 1FOOOO
>>> c

VAX-11/725 and VAX-11/730

The following console commands cause a system failure on a VAX-11/725
or a VAX-11/730 (as well as on VAXstation II systems and MicroVAX 2000
systems). CTRL/P automatically halts the processor.
$ lcTRL/P I
>>> H

»> E PSL
»> E/I/N:4 0
>>> D PC FFFFFFFF
>» D PSL 1FOOOO
>>> c

SDA-31

SDA Usage Summary
The System Dump Analyzer is a utility that you can use to help determine
the causes of system failures. This utility is also useful for examining the
running system.

FORMAT

ANALYZE

/CRASH_DUMP [/RELEASE] filespec ]
[ /SYSTEM
/SYMBOL=system-symbol-table

COMMAND
PARAMETER

usage summary

files pee
Name of the file that contains the dump you want to analyze. At least one
field of the filespec is required, and it can be any field. The default filespec
is the highest version of SYSDUMP.DMP in your default directory.
You invoke SDA to analyze a system dump by issuing the command
$ ANALYZE/CRASH_DUMP filespec

If you do not specify filespec, SDA prompts you for it.

To analyze a crash dump, your process must have the privileges
necessary for reading the dump file. This usually requires system
privilege (SYSPRV), but your system manager can, if necessary, allow
less privileged processes to read the dump files. Your process needs
change-mode-to-kernel (CMKRNL) privilege to release page file dump
blocks, whether you use the /RELEASE qualifier or the SDA COPY
command.
You invoke SDA to analyze a running system by issuing the command
$ ANALYZE/SYSTEM

To examine a running system, your process must have change-mode-tokernel (CMKRNL) privilege. You cannot specify filespec when using the
/SYSTEM qualifier.
To send all output from SDA to a file, use the SDA command SET OUTPUT,
specifying the name of the output file. The file produced is 132 columns wide
and is formatted for output to a printer. To later redirect the output to your
terminal, use the command
$ SET OUTPUT SYS$0UTPUT

To send a copy of all the commands you type and all the output those
commands produce to a file use the SDA command SET LOG, specifying the
name of the log file. The file produced is 132 columns wide and is formatted
for output to a printer.

SDA-32

SDA Usage Summary

To exit from SDA, use the EXIT command. Note that the EXIT command also
causes SDA to exit from display mode. Thus, if SDA is in display mode, you
must use the EXIT command twice: once to exit from display mode, and a
second time to exit from SDA.

SDA-33

SYSTEM DUMP ANALYZER
SDA Qualifiers

SDA
QUALIFIERS

The qualifiers described in the following section determine whether the object
of an SDA session is a crash dump or a running system and help create the
environment of an SDA session.
/CRASH_DUMP
/RELEASE
/SYMBOL
/SYSTEM

SDA-34

SYSTEM DUMP ANALYZER
/CRASH_DUMP

/CRASH_DUMP
Invokes SDA to analyze the specified dump file.

FORMAT
PARAMETER

/CRASH_DUMP

filespec

files pee
Name of the crash dump file to be analyzed. The default file specification is
SYS$DISK:[default-dir]SYSDUMP.DMP
SYS$DISK and [default-dir] represent the disk and directory specified in your
last SET DEFAULT command. If you do not specify filespec, SDA prompts
you for it.

DESCRIPTION

See Section 2 for additional information on crash dump analysis.

EXAMPLES
iJ

$ ANALYZE/CRASH_DUMP SYS$SYSTEM:SYSDUMP.DMP
$ ANAL/CRASH SYS$SYSTEM

These commands invoke SDA to analyze the crash dump stored in
SYS$SYSTEM:SYSDUMP.DMP.
~

$ANAL/CRASH SYS$SYSTEM:PAGEFILE.SYS

This command invokes SDA to analyze a crash dump stored in the system
paging file.

SDA-35

SYSTEM DUMP ANALYZER
/RELEASE

/RELEASE
Invokes SDA to release those blocks in the specified system paging file
occupied by a crash dump.

FORMAT
PARAMETER

/RELEASE

filespec

files pee
Name of the system page file (SYS$SYSTEM:PAGEFILE.SYS). The default file
specification is

SYS$DISK:[default-dir]SYSDUMP. DMP
SYS$DISK and [default-dir] represent the disk and directory specified in your
last SET DEFAULT command. If you do not specify filespec, SDA prompts
you for it.

DESCRIPTION

You use the /RELEASE qualifier to release from the system paging file
those blocks occupied by a crash dump. When invoked with the /RELEASE
qualifier, SDA immediately deletes the dump from the paging file and allows
no opportunity to analyze its contents.
When you specify the /RELEASE qualifier in the ANALYZE command, you
must also
1

Use the /CRASH_DUMP qualifier.

Include the name of the system paging file
(SYS$SYSTEM:PAGEFILE.SYS) as the filespec.

If you do not specify the system paging file or the specified paging file does

not contain a dump, SDA generates the following messages:
%SDA-E-BLKSNRLSD, no dump blocks in page file to release, or not page file
%SDA-E-NOTPAGFIL, specified file is not the page file

EXAMPLE
$ ANALYZE/CRASH_DUMP/RELEASE SYS$SYSTEM:PAGEFILE.SYS
$ ANALYZE/CRASH/RELEASE PAGEFILE.SYS

These commands invoke SDA to release to the paging file those blocks in
SYS$SYSTEM:P AGEFILE.SYS occupied by a crash dump.

SDA-36

SYSTEM DUMP ANALYZER
/SYMBOL

/SYMBOL
Specifies a system symbol table for SDA to use in place of the system
symbol table it uses by default (SYS$SYSTEM:SYS.STB).

FORMAT
PARAMETER

/SYMBOL =system-symbol-table
system-symbol table
File specification of the VMS SDA system symbol table needed to define
symbols required by SDA to analyze a dump from a particular VMS system.
The specified system-symbol-table must contain those symbols required by
SDA to find certain locations in the executive image.
If you do not specify the /SYMBOL qualifier, SDA uses

SYS$SYSTEM:SYS.STB by default. When you do specify the /SYMBOL
qualifier, SDA assumes the default disk and directory to be SYS$DISK: that is,
the disk and directory specified in your last SET DEFAULT command. If SDA
is given a file that is not a system symbol table in the /SYMBOL qualifier, it
halts with a fatal error.

DESCRIPTION

The /SYMBOL qualifier allows you to specify a system symbol table, other
than SYS$SYSTEM:SYS.STB, to load into the SDA symbol table. This may be
necessary, for instance, in order to analyze a crash dump taken on a processor
running a different version of VMS.
You can use the /SYMBOL qualifier whether you are analyzing a system
dump or a running system.

EXAMPLE
$ ANALYZE/CRASH_DUMP/SYMBOL=SYS$CRASH:SYS.STB SYS$SYSTEM

This command invokes SDA to analyze the crash dump stored in
SYS$SYSTEM:SYSDUMP.DMP, using the system symbol table at
SYS$CRASH:SYS.STB.

SDA-37

SYSTEM DUMP ANALYZER
/SYSTEM

/SYSTEM
Invokes SDA to analyze a running system.

FORMAT

/SYSTEM

PARAMETERS

None.

DESCRIPTION

See Section 3 for a full discussion of using SDA to analyze a running system.
You cannot specify the /CRASH_DUMP or /RELEASE qualifiers when you
include the /SYSTEM qualifier in the ANALYZE command.

EXAMPLE
$

ANALYZE/SYSTEM

This command invokes SDA to analyze the running system.

SDA-38

SYSTEM DUMP ANALYZER
SDA Commands

SDA
COMMANDS

The commands described in the following section can be used in analyzing a
system dump or the running system.
@(Execute Procedure)
ATTACH
COPY
DEFINE
EVALUATE
EXAMINE
EXIT
FORMAT
HELP
READ
REPEAT
SEARCH
SET CPU
SET LOG
SET OUTPUT
SET PROCESS
SET RMS
SHOW CALL_FRAME
SHOW CLUSTER
SHOW CONNECTIONS
SHOW CPU
SHOW CRASH
SHOW DEVICE
SHOW EXECUTIVE
SHOW HEADER
SHOW LOCK
SHOW PAGE_TABLE
SHOW PFN_DATA
SHOW POOL
SHOW PORTS
SHOW PROCESS
SHOW RESOURCE
SHOW RMS
SHOW RSPID
SHOW SPINLOCKS
SHOW STACK
SHOW SUMMARY
SHOW SYMBOL
SPAWN
VALIDATE QUEUE

SDA-39

SYSTEM DUMP ANALYZER
@ (Execute Procedure)

@ (Execute Procedure)
Causes SDA to execute SDA commands contained in a file. Use this
command to execute a set of frequently used SDA commands.

FORMAT
PARAMETER

@files pee
file spec
Name of a file that contains the SDA commands to be executed. The default
file type is COM.

EXAMPLE
SDA> @USUAL

The Execute Procedure command executes the following commands, as
contained in a file named USUAL.COM:
SET OUTPUT LASTCRASH.LIS
SHOW CRASH
SHOW PROCESS
SHOW STACK
SHOW SUMMARY
EXIT

This command procedure first makes the file LASTCRASH.LIS the destination
for output generated by subsequent SDA commands. Next, the command
procedure sends to the file information about the crash and its context, a
description of the process executing at the time of the process, the contents
of the stack on which the crash occurred, and a list of the processes active on
the CPU that crashed. Finally, it exits from SDA.
The procedure need not exit from the utility at the end of its execution. To
continue using SDA interactively after the execution of a command procedure,
omit the EXIT command from the file.

SDA-40

SYSTEM DUMP ANALYZER
ATTACH

ATTACH
Switches control of your terminal from your current process to another
process in your job.

FORMAT
PARAMETER

QUALIFIER

ATTACH

process-name

process-name
Name of the process to which you want to transfer control.

/PARENT
Transfers control of the terminal to the current process's parent process.
When you specify this qualifier, you cannot specify the process-name
parameter.

EXAMPLES

SDA> ATTACH/PARENT

This ATTACH command attaches the terminal to the parent process of the
current process.
~

SDA> ATTACH DUMPER

This ATTACH command attaches the terminal to a process named DUMPER
in the same job as the current process.

SDA-41

SYSTEM DUMP ANALYZER
COPY

COPY
Copies the contents of the dump file to another file.

FORMAT
PARAMETER

COPY

output-filespec

output-filespee
Name of the device, directory, and file to which SDA copies the dump file.
The default file specification is

SYS$D ISK:[ default-dir] filename. DMP
SYS$DISK and [default-dir] represent the disk and directory specified in your
last SET DEFAULT command. You must at least supply the file name.

DESCRIPTION

Each time the system fails, the system copies the contents of physical
memory and the hardware context of the current process (as directed by
the DUMPSTYLE parameter) into the file SYS$SYSTEM:SYSDUMP.DMP (or
the paging file), overwriting its contents. If you do not save this crash dump
elsewhere, it will be overwritten the next time that the system fails.
The COPY command allows you to preserve a crash dump by copying its
contents to another file. It is generally useful to invoke SDA during system
initialization (from within SYS$MANAGER:SYSTARTUP.COM) to execute
the COPY command. This ensures that a copy of the dump file is made each
time the system fails.
The COPY command does not affect the contents of
SYS$SYSTEM:SYSDUMP.DMP.
If you are using the paging file (SYS$SYSTEM:P AGEFILE.SYS) as the dump

file instead of SYSDUMP.DMP, you can use the COPY command to explicitly
release the blocks of the paging file that contain the dump, thus making them
available for paging. Although the copy operation succeeds nonetheless,
the release operation requires that your process have change-mode-to-kernel
(CMKRNL) privilege. Once the dump pages have been released from the
paging file, the dump information in these pages may be lost. You should
perform subsequent analysis upon the copy of the dump created by the COPY
command.

EXAMPLE
SDA> COPY SYS$CRASH:SAVEDUMP

The COPY command copies the dump file into the file
SYS$CRASH:SAVEDUMP.DMP.

SDA-42

SYSTEM DUMP ANALYZER
DEFINE

DEFINE
Assigns a value to a symbol, or associates an SDA command with a
terminal key.

FORMAT

PARAMETERS

DEFINE

symbol-name[=] expression
J
[ /KEY key-name command [/qualifier ... }

symbol-name
Name, containing from 1 to 31 alphanumeric characters, that identifies the
symbol. See 5.2.4 for a description of SDA symbol syntax and a list of default
symbols.

expression
Definition of the symbol's value. See Section 5.2 for a discussion of the
components of SDA expressions.

key-name
Name of the key to be defined. You can define the following keys under
SDA:
Key Name

Key Designation

PF1

LK201 , VT 100, VT52 Red

PF2

LK201, VT100, VT52 Blue

PF3

LK201 , VT 100, VT52 Black

PF4

LK201, VT100

KPO ... KP9

Keypad 0-9

PERIOD

Keypad period

COMMA

Keypad comma

MINUS

Keypad minus

ENTER

Keypad ENTER

Up arrow

DOWN

Down arrow

LEFT

Left arrow

RIGHT

Right arrow

LK201 Find

LK201 Insert Here

LK201 Remove

LK201 Select

LK201 Prev Screen

LK201 Next Screen

SDA-43

SYSTEM DUMP ANALYZER
DEFINE

Key Name

Key Designation

HELP

LK201 Help

LK201 Do

F7 ... F20

LK201 Function keys

command
SDA command the key is to be defined as. The command must be enclosed
in quotation marks ("").

QUALIFIERS

/ECHO
/NOECHO
Determines whether the equivalence string is displayed on the terminal screen
after the defined key has been pressed. The /NOECHO qualifier functions
only with the /TERMINATE qualifier. The default is /ECHO.

/IF_STATE=(state-name, ... )
/NOIF_STATE
Specifies a list of one or more states, one of which must be in effect for the
key definition to be in effect. States are placed in effect by the /SET_STATE
qualifier, a description of which appears below.
The state-name is an alphanumeric string, enclosed in quotation marks ("").
By including several state names, you can define a key to have the same
function in all the specified states. If you specify only one state name, you
can omit the parentheses.
If you omit the /ILSTATE qualifier-or use /NOILSTATE-the current
state is used.

/KEY
Defines a key as an SDA command. Subsequently, you need only press the
defined key and the RETURN key to issue the command. If you use the
/TERMINATE qualifier as well, you need not press the RETURN key.
When you define some keys as SDA commands, you must press CTRL/V
before those keys to execute the commands. This is because of the escape
sequences these keys generate, and the way the terminal driver handles those
escape sequences. The following keys, when defined as SDA commands,
must be preceded by a CTRL/V.
Key Name

Key Designation

LEFT

Left arrow

RIGHT

Right arrow

F7 ... F14

LK201 function keys

/SET_STATE=state-name
Causes the key being defined to cause a key state change rather than issue
an SDA command. When you use the /SET_STATE qualifier, you supply the
name of a key state in place of the key-name parameter. In addition, you
must define the command parameter as a pair of quotation marks('"').

SDA-44

SYSTEM DUMP ANALYZER
DEFINE

The key state can be any name you think appropriate. For example, you can
define the PFl key to set the state to gold and use the /IF_STATE=GOLD
qualifier to allow two definitions for the other keys, one in the gold state and
one in the nongold state.

/TERMINATE
/NOTERMINATE
Causes the key definition to include termination of the command, which
causes SDA to execute the command when the defined key is pressed.
Therefore, you do not have to press the RETURN key after you press the
defined key if the /TERMINATE qualifier is specified.

DESCRIPTION

The DEFINE command causes SDA to evaluate an expression and then assign
its value to a symbol. Both the DEFINE and EVALUATE commands perform
computations in order to evaluate expressions. DEFINE adds symbols to
the SDA symbol table but does not display the results of the computation.
EVALUATE displays the result of the computation but does not add symbols
to the SDA symbol table.
The DEFINE/KEY command causes an SDA command to be associated with
the specified key, in accordance with any of the specified qualifiers described
previously.
If the symbol or key is already defined, SDA replaces the old definition with

the new one. Symbols and keys remain defined until you exit from SDA.

EXAMPLES
iJ

SDA>
SDA>
SDA>

DEFINE BEGIN = 80058EOO
DEFINE END = 80058E60
EXAMINE BEGIN:END

In the preceding example, DEFINE defines two addresses, called BEGIN and
END. These symbols serve as reference points in memory, defining a range of
memory locations that the EXAMINE command can inspect.
~

SDA> DEFINE NEXT = ©PC
SDA> EXAMINE/INSTRUCTION NEXT
NEXT:
MOVL ©OO(R6) ,RO

Symbol NEXT defines the address contained in the program counter, so that
the symbol can be used in an EXAMINE/INSTRUCTION command.
~

SDA> DEFINE VEC SCH$GL_PCBVEC
SDA> EXAMINE VEC
SCH$GL_PCBVEC: 80B7D31C ".0 .. "

After the value of global symbol SCH$GL _PCBVEC has been assigned to
the symbol VEC, the symbol VEC is used to examine the memory location or
value represented by the global symbol.

SDA-45

SYSTEM DUMP ANALYZER
DEFINE

SDA> DEFINE COUNT = 7
SDA> DEFINE RESULT = COUNT * COUNT
SDA> EVALUATE RESULT
Hex = 00000031
Decimal = 49
PR$_SBIS
RESULT

The first DEFINE command assigns symbol COUNT the value 7. The second
DEFINE command then defines RESULT to be the result of the evaluation of
an arithmetic expression using the symbol COUNT. Evaluation of RESULT
shows that system symbol PR$_SBIS has an equivalent value.
SDA> DEFINE/KEY PF1 "SHOW STACK"
SDA> ltf_l] SHOW STACK [!3ET~RN]
Process stacks (on CPU 00)
Current operating stack (KERNEL) :

SP =>

7FFE8DD4
7FFE8DD8
7FFE8DDC
7FFE8DEO
7FFE8DE4
7FFE8DE8
7FFE8DEC
7FFE8DFO

00001703
80127920
00000000
00000000
00000000
00000000
7FF743E4
7FF743CC

SGN$C_MAXPGFL+703

7FFE8DF4
7FFE8DF8
7FFE8DFC

8000E646
7FFEDE96
03COOOOO

EXE$CMODEXEC+1EE
SYS$CMKRNL+006

The DEFINE/KEY command defines PFl as the SHOW STACK command.
When the PFl key is pressed, SDA displays the command and waits for a
carriage return to be entered.
SDA> DEFINE/KEY /TERMINATE PF1 "SHOW STACK"
SDA> if_[[j SHOW STACK
Process stacks (on CPU 00)
Current operating stack (KERNEL) :

The DEFINE/KEY command defines PFl as the SDA SHOW STACK
command. The use of the /TERMINATE qualifier causes SDA to execute
the SHOW STACK command without waiting for a carriage return to be
entered.

SDA> DEFINE/KEY /SET_STATE~~ 11 GREEN 11 PF1 1111
SDA> DEFINE/KEY /TERMINATE/IF __ STATE=GREEN PF3 "SHOW STACK"
SDA> [Pf1] [PF3\ SHOW STACK
Process stacks (on CPU 00)
Current operating stack (KERNEL):

The first DEFINE command defines PFl as a key that sets a command state
GREEN. The trailing pair of quotation marks is required syntax, indicating
that no command is to be executed when this key is pressed.

SDA-46

SYSTEM DUMP ANALYZER
DEFINE

The second DEFINE command defines PF3 as the SHOW STACK command,
but, using the /IF-STATE qualifier, makes the definition valid only when the
command state is GREEN. Thus, the user must press PFl before pressing PF3
to issue the SHOW STACK command. The /TERMINATE qualifier causes the
command to execute as soon as the PF3 key is pressed.

SDA-47

SYSTEM DUMP ANALYZER
EVALUATE

EVALUATE
Computes and displays the value of the specified expression in both
hexadecimal and decimal. Alternative evaluations of the expression are
available with the use of the qualifiers defined for this command.

FORMAT
EVALUATE

/CONDITION_ VALUE
/PSL
/PTE

·
express10n

/SYMBOLS

PARAMETER

expression
SDA expression to be evaluated. Section 5.2 describes the components of
SDA expressions.

QUALIFIERS

/CONDITION_ VALUE
Displays the message that the $GETMSG system service obtains for the value
of the expression.

/PSL
Evaluates the specified expression in the format of a processor status
longword.

/PTE
Interprets and displays the expression as a page table entry (PTE). The
individual fields of the PTE are separated and an overall description of the
PTE's type is provided.

/SYMBOLS
Specifies that all symbols that are known to be equal to the evaluated
expression are to be listed in alphabetical order. The default behavior of
the EVALUATE command displays only the first several such symbols.

DESCRIPTION

If the expression is equal to the value of a symbol in the SDA symbol table,
that symbol is displayed. If no symbol with this value is known, the next
lower valued symbol is displayed with an appropriate offset if the offset is

small enough for the selected symbol to be considered useful.

EXAMPLES
iJ

SDA> EVALUATE -1
Hex = FFFFFFFF
Decimal = -1

PR$_XSID_N8NNN

The EVALUATE command evaluates a numeric expression, displays the
value of that expression in hexadecimal and decimal notation, and displays a
symbol that has been defined to have an equivalent value.

SDA-48

SYSTEM DUMP ANALYZER
EVALUATE

SDA> EVALUATE 1
Hex = 00000001
Decimal = 1

ACP$V_SWAPGRP
ACP$V_WRITECHK
EVT$_EVENT

The EVALUATE command evaluates a numeric expression and displays the
value of that expression in hexadecimal and decimal notation. The preceding
example also shows the symbols that have the displayed value. A finite
number of symbols are displayed by default.
SDA> DEFINE TEN = A
SDA> EVALUATE TEN
Hex = OOOOOOOA Decimal = 10

EXE$V_FATAL_BUG
SGN$C_MINWSCNT
TEN

The preceding example shows the definition of a symbol named TEN. The
EVALUATE command then shows the value of the symbol.
Note that A, the value assigned to the symbol by the DEFINE command,
could be a symbol. When SDA evaluates a string that can be either a symbol
or a hexadecimal numeral, it first searches its symbol table for a definition of
the symbol. If SDA finds no definition for the string, it evaluates the string as
a hexadecimal number.
~

SDA> EVALUATE (((TEN * 6) + (-1/4))
Hex = 00000042
Decimal = 66

The preceding example shows how SDA evaluates an expression of several
terms, including symbols and rational fractions. SDA evaluates the symbol,
substitutes its value in the expression, and then evaluates the expression.
Note that the fraction -1/4 is truncated to 0.
~

SDA> EVALUATE/CONDITION 80000018
%SYSTEM-W-EXQUOTA, exceeded quota

The preceding example shows the output of an EVALUATE/CONDITION
command.
~

SDA> EVALUATE/PSL 04080009
CMP TP FPO IS CURMOD PRVMOD IPL DV FU IV T N Z V C
0 0 0 1 KERN
KERN
08 0 0 0 0 1 0 0 1

SDA interprets the entered value 04080009 as though it were a processor
status longword (PSL) and displays the resulting field values of that
longword.

SDA-49

SYSTEM DUMP ANALYZER
EVALUATE

SDA> EVALUATE/PTE ABCDFFEE

131
I

28127
I

24123
I

20119
I

16I15
I

12111
I

817
I

+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-->

11 I O 1 O 1

IO 1--1 1 1 1--1 OI

ODFFEE

+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-->

Vld

Prot= EW

Own=U

Page Frame Number

Page is Active and Valid

The EVALUATE/PTE command displays the expression ABCDFFEE as a page
table entry (PTE) and labels the fields. It also describes the status of the page.

SDA-50

SYSTEM DUMP ANALYZER
EXAMINE

EXAMINE
Displays the contents of a location or range of locations in physical
memory or the contents of a register. You can use location parameters
to display specific locations or use qualifiers to display entire process and
system regions of memory.

FORMAT
PARAMETER

EXAMINE [/qualifier{, .. .}] [location}
location
Location in memory to be examined. A location can be represented by any
valid SDA expression (see Section 5.2). To examine a range of locations, the
following syntax is used:
m:n
m;n

Range of locations to be examined, from m to n
Range of locations to be examined, starting at m and continuing for n
bytes

The default location that SDA uses is initially 0 in the program region
(PO) of the process that was executing at the time the system failed (if you
are examining a crash dump) or your process (if you are examining the
running system). Subsequent uses of the EXAMINE command with no
parameter specified increase the last address examined by 4. Use of the
/INSTRUCTION qualifier increases the default address as appropriate to
the translation of the instruction. To examine memory locations of other
processes, you must use the SET PROCESS command.

QUALIFIERS

/ALL
Examines all the locations in the program and control regions and parts of the
writable system region, displaying the contents of memory in hexadecimal
longwords. Do not specify parameters when you use this qualifier.

/CONDITION_ VALUE
Examines the specified longword, displaying the message the $GETMSG
system service obtains for the value in the longword.

/INSTRUCT/ON
Translates the contents of the specified range of memory locations into
VAX MACRO instruction format. If more than 16 bytes are specified in the
range, /INSTRUCTION processing may skip some bytes at the beginning
of the range to ensure that SDA is properly synchronized with the start of
each instruction. This synchronization may be overridden by specifying the
/NOS KIP qualifier.
The length of the instruction displayed varies according to the opcode and
addressing mode. If SDA cannot decode a memory location, it issues the
following message:
%SDA-E-NOINSTRAN, cannot translate instruction

SDA-51

SYSTEM DUMP ANALYZER
EXAMINE

When you use this qualifier with the EXAMINE command, SDA calculates
subsequent default addresses by adding the length of the last instruction,
including all operands, to the last address examined.

/NOSKIP
Causes the EXAMINE command not to skip any bytes in the range when
translating the contents of memory into VAX MACRO instructions. The
/NOSKIP qualifier causes the execution of the /INSTRUCTION qualifier by
default.

/NOSUPPRESS
Inhibits the suppression of zeros when displaying memory with one of the
following qualifiers: /ALL, /PO, /Pl, /SYSTEM.

/PO
Displays the entire program region for the default process. Do not specify
parameters when you use this qualifier.

/P1
Displays the entire control region for the default process. Do not specify
parameters when you use this qualifier.

/PSL
Examines the specified longword, displaying its contents in the format of a
processor status longword. This qualifier must precede any parameters used
in the command line.

/PTE
Interprets and displays the specified longword as a page table entry (PTE).
The display separates individual fields of the PTE and provides an overall
description of the PTE's type.

/SYSTEM
Displays portions of the writable system region. Do not specify parameters
when you use this qualifier.

/TIME
Examines the specified quadword, displaying its contents in the format of a
system-date-and-time quadword.

DESCRIPTION

The following sections describe how to use the EXAMINE command.
Examining Locations

When you use the EXAMINE command to look at a location, SDA displays
the location: in symbolic notation (symbolic name plus offset), if possible, and
its contents in hexadecimal and ASCII formats:
SDA> EXAMINE G6605CO
806605CO: 80002119 II. ! .. "

If the ASCII character that corresponds to the value contained in a byte is not
printable, SDA displays a period character (. ). If the specified location does

not exist in memory, SDA displays the message
%SDA-E-NOTINPHYS, address : not in physical memory

SDA-52

SYSTEM DUMP ANALYZER
EXAMINE

To examine a range of locations, you can designate starting and ending
locations separated by a colon. For example:
SDA> EXAMINE G40:G200

Alternatively, you can specify a location and a length, in bytes, separated by
a semicolon. For example:
SDA> EXAMINE G400;16

When used to display the contents of a range of locations, the EXAMINE
command displays six columns of information:
•

Each of the first four columns represents a longword of memory, the
contents of which are displayed in hexadecimal format.

•

The fifth column lists the ASCII value of each byte in each longword
displayed in the previous four columns.

•

The sixth column contains the address of the first, or rightmost, longword
in each line. This address is also the address of the first, or leftmost,
character in the ASCII representation of the longwords. Thus, you read
the hexadecimal dump display from right to left, and the ASCII display
from left to right.

If a series of virtual addresses does not exist in physical memory, SDA
displays a message specifying the range of addresses that were not translated.

For example:
SDA> EXAMINE 100:200
Virtual locations 00000100 through 000001FF are not in physical memory
0130011A 01200118 0130011E 0110011F
01200107 02300510 04310216 04210218
01100103 01100104 01200105 01200106

...... 0 . . . . . . 0.
.. ! ... 1 ... 0 ... .

00000200
00000210
00000220

Addresses 100 16 through 1FF 16 do not exist in memory, as the message
indicates. SDA displays the contents of those addresses that do exist (200 16
through 22016)·
If a range of virtual locations contains only zeros, SDA displays the message
Zeros suppressed from 'loci' to 'loc2'

Decoding Locations

You can translate the contents of memory locations into VAX MACRO
instruction format by using the /INSTRUCTION qualifier. This qualifier
causes SDA to display the location in symbolic notation (if possible) and its
contents in instruction format. The operands of decoded instructions are also
displayed in symbolic notation.
If the specified range of locations does not begin on an instruction boundary,
SDA skips bytes until it locates the next valid instruction, and issues the
message
%SDA-W-INSKIPPED, unreasonable instruction stream - n bytes skipped

In this message, n represents the number of bytes that SDA could not
translate.

SDA-53

SYSTEM DUMP ANALYZER
EXAMINE

Examining Memory Regions

You can display an entire region of virtual memory by using one or more of
the qualifiers/ ALL, /SYSTEM, /PO, and Pl with the EXAMINE command.
Other Uses

Other uses of the EXAMINE command appear in the following examples.

EXAMPLES

SDA> EXAMINE/SYSTEM
System Region Memory
00040039 8FBC0010 00040038 8FBC0010

.... 8 ....... 9 .. .

800000000

The preceding example shows only the first two lines of the display generated
by the EXAMINE/SYSTEM command. Note that in the dump the fifth byte
from the right contains the value 38 16 . The ASCII value of 38 16 , the character
8, is represented in the fifth character from the left in column 5.
Likewise, the 13th byte from the right in the dump columns contains the
value 39 16 . The ASCII value of 39 16 is 9, and 9 is represented in the ASCII
column as the 13th character from the left.
~

SDA> EXAMINE/PSL G1268
CMP TP FPD IS CURMOD PRVMOD IPL DV FU IV T N Z V C
1 0 0 0 KERN
KERN
00 0 1 0 1 1 1 0 0

The preceding example shows the display produced by the EXAMINE/PSL
command. The address of the longword examined is 80001268 16 .
~

SDA> EXAMINE/PTE G775F480

28127
I

131
I

20119
I

24123
I

16I15
I

12111
I

817
I

+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-->

11 I

1 1 1 o 11 1--1 o o 1--1 OI

OOFOF4

+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-->

Vld

Prot= URKW M

Own=K

Page Frame Number

Page is Active and Valid

The EXAMINE/PTE command displays and formats the system page table
entry at 8775F48016·
~

SDA> EXAMINE/TIME EXE$GQ_SYSTIME
18-FEB-1989 02:07:25.88

The EXAMINE/TIME command displays the formatted value of the system
time quadword (EXE$GQ_SYSTIME).

SDA-54

SYSTEM DUMP ANALYZER
EXIT

EXIT
Exits from an SDA display or exits from the SDA utility.

FORMAT

EXIT

PARAMETERS

None.

QUALIFIERS

None.

DESCRIPTION

If SDA is displaying information on a video display terminal-and if that

information extends beyond one screen-SDA displays a screen overflow
prompt at the bottom of the screen: 5
Press RETURN for more.
SDA>

If you want to discontinue the current display at this point, type EXIT. If

you want SDA to execute another command, type that command. SDA
discontinues the display as if you typed EXIT, and then executes the
command you typed.
When the SDA> prompt is not immediately preceded by the screen overflow
prompt, typing EXIT causes your process to cease executing the SDA utility.

On hardcopy terminals, SDA does not display such a prompt.

SDA-55

SYSTEM DUMP ANALYZER
FORMAT

FORMAT
Displays a formatted list of the contents of a block of memory.

FORMAT
PARAMETER

FORMAT [/qualifier} location
location
Location of the beginning of the data block. The location can be given as any
valid SDA expression.

QUALIFIER

/TYPE=block-type
Forces SDA to characterize and format a data block at location as the
specified type of data structure. The /TYPE qualifier thus overrides the
default behavior of the FORMAT command in determining the type of a data
block, as described below. The block-type can be the symbolic prefix of any
data structure defined by VMS.

DESCRIPTION

The FORMAT command performs the following actions:
•

Characterizes a range of locations as a system data block

•

Assigns, if possible, a symbol to each item of data within the block

•

Displays all the data within the block

Normally, you use the FORMAT command without the /TYPE qualifier.
Used in this manner, it examines the byte in the structure that contains the
type of the structure. In most VMS data structures, this byte occurs at an
offset of OA 16 into the structure. If this byte does not contain a valid block
type, the FORMAT command halts with the message
%SDA-E-INVBLKTYP, invalid block type in specified block

However, if this byte does contain a valid block type, SDA checks the next
byte (offset OB 16 ) for a secondary block type. When SDA has determined
the type of block, it searches for the symbols that correspond to that type of
block.

If SDA cannot find the symbols associated with the block type it has found
(or you specified in the /TYPE qualifier), it issues the message
No "block-type" symbols found to format this block

If you receive this message, you may want to read additional symbols into
the SDA symbol table and retry the FORMAT command. Most symbols that
define VMS data structures are contained within SYS$SYSTEM:SYSDEF.STB.
Thus, you would issue the command
SDA> READ SYS$SYSTEM:SYSDEF.STB

SDA-56

SYSTEM DUMP ANALYZER
FORMAT

Certain VMS data structures do not contain a block type at offset OA 16 . If
this byte contains information other than a block type-or the byte does not
contain a valid block type-SDA produces the message
Invalid block type in specified block

To format such a block, you must reissue the FORMAT command, using the
/TYPE qualifier to designate a block-type.
The FORMAT command produces a three-column display:
•

The first column shows the virtual address of each item within the block.

•

The second lists each symbolic name associated with a location within the
block.

•

The third shows the contents of each item in hexadecimal format.

EXAMPLE
SDA> READ SYS$SYSTEM:SYSDEF.STB
SDA> FORMAT 800B81FO
800B81FO UCB$L_FQFL
UCB$L_RQFL
UCB$W_MB_SEED
UCB$W_UNIT_SEED
UCB$L_FQBL
800B81F4
UCB$L_RQBL
800B81F8 UCB$W_SIZE
800B81FA UCB$B_TYPE
UCB$B_FLCK
800B81FB
800B81FC UCB$L_ASTQFL
UCB$L_FPC
UCB$T_PARTNER
800B8200 UCB$L_ASTQBL
UCB$L_FR3
800B8204 UCB$L_FIRST
UCB$L_FR4
UCB$W_MSGMAX
UCB$W_MSGCNT

80000F10

800026A8
OOEO
10
07
800F80EO
8002CF80
8002CAOO

The READ command loads into SDA's symbol table the symbols from
SYS$SYSTEM:SYSDEF.STB needed for formatting system data structures. The
FORMAT command displays the data structure that begins at 800B81F0 16 ,
a unit control block (UCB). If a field has more than one symbolic name, all
such names are displayed. Thus, the field that starts at 800B8204 16 has three
designations: UCB$L_FIRST and UCB$L_FR4, alternative names for the
longword; and the two subfields, UCB$W_MSGMAX and UCB$W_MSGCNT.
The contents of each field appear to the right of the symbolic name of the
field. Thus, the contents of UCB$L_FIRST are 8002CA00 16 .

SDA-57

SYSTEM DUMP ANALYZER
HELP

HELP
Displays information about the SDA utility, its operation, and the format of
its commands.

FORMAT
PARAMETER

HELP [command-name}
command-name
Command for which you need information.
You can also specify the following keywords in place of command-name:
Keyword

Function

CPU_CONTEXT

Describes the concept of CPU context as it governs the
behavior of SDA in uniprocessor and multiprocessor
environments

EXPRESSIONS

Prints a description of SDA expressions

INITIALIZATION

Describes the circumstances under which SDA executes
an initialization file when first invoked

OPERATION

Describes how to operate SDA at your terminal and by
means of the site-specific startup procedure

PROCESS_CONTEXT

Describes the concept of process context as it governs
the behavior of SDA in uniprocessor and multiprocessor
environments

QUALIFIERS

None.

DESCRIPTION

The HELP command displays brief descriptions of SDA commands and
concepts on the terminal screen (or sends these descriptions to the file
designated in a SET OUTPUT command). You can request additional
information by specifying the name of a topic in response to the Topic?
prompt.
If you do not specify a parameter in the HELP command, it lists those

commands and topics for which you can request help, as follows:
Information available:
ATTACH
COPY
Execute_Command
Initialization
SEARCH
SET
Topic?

SDA-58

CPU_Context
DEFINE
EXIT
Expressions
Operation Process_Context
SHOW
SPAWN
Symbols

EVALUATE
FORMAT
READ
VALIDATE

EXAMINE
HELP
REPEAT

SYSTEM DUMP ANALYZER
READ

READ
Loads the global symbols contained in the specified object module into the
SDA symbol table.

FORMAT

PARAMETER

READ

/EXECUTIVE directory-spec
}
{ [/RELOCATE=expression] filespec

filespec
Name of the device, directory, and file that contains the object module
from which you want to copy global symbols. The filespec defaults to
SYS$DISK:[default-dir]filename.STB, where SYS$DISK and [default-dir] represent
the disk and directory specified in your last SET DEFAULT command. You
must specify a file name.

QUALIFIERS

/EXECUTIVE directory-spec
Reads into the SDA symbol table all global symbols and global entry
points defined within all loadable images that make up the executive. (See
Table SDA-5 for a list of these images.)
The directory-spec is the name of the directory containing the loadable
images of the executive; this parameter defaults to SYS$LOADABLE_
IMAGES.

/RELOCATE=expression
Adds the value of expression to the value of each symbol in the symbol-table
file to be read. You can use the /RELOCATE qualifier only if you also specify
a filespec. The /RELOCATE qualifier is useful for examining images that are
position independent and are loaded at a base of zero.

DESCRIPTION

The READ command symbolically identifies locations in memory for which
the default symbol table (SYS$SYSTEM:SYS.STB) provides no definition. In
other words, the required global symbols are located in modules that have
been compiled and linked separately from the VMS executive. 6
The object module file specified in the READ command can be one of the
following:

•

Output of a compiler or assembler (for example, an .OBJ file)

•

Output generated by the linker qualifier /SYMBOL_TABLE (for example,
an .STB file)

SDA extracts no local symbols from the object module.

SDA-59

SYSTEM DUMP ANALYZER
READ

Most often the object module file is a file provided by VMS in directory
SYS$SYSTEM or SYS$LOADABLE_IMAGES. Many SDA applications, for
instance, need to load the definitions of system data structures by issuing a
READ command specifying SYS$SYSTEM:SYSDEF.STB. Others require the
definitions of specific global entry points within the executive image that are
contained within those object modules included in the executive.
Table SDA-4 lists those object module files VMS provides in SYS$SYSTEM.
Table SDA-5 lists those loadable images in SYS$LOADABLE_IMAGES that
define locations within the VMS executive image.
Table SDA-4
File

Contents

CLUSTRLOA.STB

Symbols for loadable V AXcluster management code

DCLDEF.STB

Symbols for the DCL interpreter

IMGDEF.STB

Symbols for the image activator

NETDEF.STB

Symbols for DECnet data structures

RMSDEF.STB

Symbols that define RMS internal and user data structures
and RMS$_xxx completion codes

SCSDEF.STB

Symbols that define data structures for system
communications services

SYSDEF.STB

Symbols that define system data structures, including the
1/0 database

Table SDA-5

SDA-60

Modules Containing Global Symbols Used by SDA

Modules Defining Global Locations Within the
Executive Image

File

Contents

CPULOA.EXE

Processor-specific data and initialization
routines

ERRORLOG.EXE

Error logging routines and system services

EVENT_FLAGS_AND_ASTS.EXE

Event flag and AST delivery routines and
system services

EXCEPTION.EXE

Bugcheck and exception handling routines
and those system services that declare
condition and exit handlers

IMAGE_MANAGEMENT .EXE

Image activator and the related system
services

IO_ROUTINES.EXE

$010 system service, related system
services (SYS$CANCEL, SYS$ASSIGN,
etc.), and supporting routines

LMF$GROUP_TABLE. EXE

Data for valid, licensed product groups

LOCKING.EXE

Lock management routines and system
services

LOGICAL _NAMES. EXE

Logical name routines and system services

SYSTEM DUMP ANALYZER
READ

Table SDA-5 (Cont.)

Modules Defining Global Locations Within the
Executive Image

File

Contents

MESSAGE_ROUTINES.EXE

System message routines and system
services (including SYS$SNDJBC and
SYS$GETTIM)

PAGE_MANAGEMENT .EXE

System pager, its supporting routines,
and page management system services
(including SYS$CRMPSC, SYS$CREDEL,
and SYS$ADJSTK)

PRIMITIVE_IO.EXE

Console 1/0 routines

PROCESS_MANAGEMENT. EXE

Scheduler, report system event, and
supporting routines and system services

RECOVERY_UNIT_SERVICES.EXE

Recovery unit system services

RMS.EXE

Global symbols and entry points for RMS

SECURITY.EXE

Security management routines and system
services

SYSDEVICE.EXE

Mailbox driver and null driver

SYSGETSYl.EXE

Get System Information system service
(SYS$GETSYI)

SYSLICENSE.EXE

Licensing system service (SYS$LICENSE)

SYSMSG.EXE

VMS system messages

SYSTEM_PRIMITIVES.EXE

Miscellaneous basic system routines,
including those that allocate system
memory, maintain system time, create fork
processes, and control mutex acquisition

SYSTEM_SYNCHRONIZATION.EXE

Routines that enforce synchronization in a
VMS multiprocessing system

WORKING_SET_
MANAGEMENT .EXE

Swapper, its supporting routines, and
working set management system services

EXAMPLES

SDA> READ SYS$SYSTEM:SYSDEF.STB
%SDA-I-READSYM, reading symbol table

SYS$COMMON: [SYSEXE]SYSDEF.STB;1

The READ command causes SDA to add all the global symbols in
SYS$SYSTEM:SYSDEF.STB to the SDA symbol table. Such symbols are
useful when you are formatting an 1/0 data structure, such as a unit control
block or an 1/0 request packet.

SDA-61

SYSTEM DUMP ANALYZER
READ

SDA> EXAM/INST EXE$QI0+2; 4
EXE$QI0+00002: CHMK
#001F
EXE$QI0+00006: RET
SDA> EXAM/INST V_EXE$QIO
%SDA-E-BADSYM, unknown symbol 11 V_EXE$QI0 11
SDA> READ/RELOCATE=IO_ROUTINES SYS$LOADABLE_IMAGES:IO_ROUTINES.EXE
%SDA-I-READSYM, reading symbol table SYS$COMMON: [SYS$LDR]IO_ROUTINES.EXE;1
SDA> EXAM/INST EXE$QI0+2;4
EXE$QI0+00002: MOVZBL 04(AP),R3
EXE$QI0+00006: CMPB
R3,#3F
SDA> EXAM/INST V_EXE$QI0+2;4
V_EXE$QI0+00002: CHMK
#001F
V_EXE$QI0+00006: RET

This SDA session shows that the initial examination of the instructions at
EXE$QI0+2 and EXE$QI0+6 produces the vector for the system service,
not the system service code itself. The subsequent READ instruction brings
into the SDA symbol table the global symbols defined for the system's 1/0
routines, including one that redefines the entry point of the system service
to be the start of the routine EXE$QIO. Thus, the second examination of the
same memory locations produces the first two instructions in the routine. The
READ command creates a special symbol, V_EXE$QIO, that points to the
system service vector.
~

SDA> SHOW STACK
Process stacks (on CPU 01)
Current operating stack (KERNEL) :
7FF8F2BO
7FF8F2B4
7FF8F2B8

806BA870
7FF8F4CO
8016F33E

PAGE_MANAGEMENT+0053E

SDA> READ/RELOCATE=PAGE_MANAGEMENT SYS$LOADABLE_IMAGES:PAGE_MANAGEMENT.EXE
%SDA-I-READSYM, reading symbol table SYS$COMMON: [SYS$LDR]PAGE_MANAGEMENT.EXE;1
SDA> SHOW STACK
Process stacks (on CPU 01)
Current operating stack (KERNEL) :
7FF8F2BO
7FF8F2B4
7FF8F2B8

806BA870
7FF8F4CO
8016F33E

MMG$LOCK_SYSTEM_PAGES+00188

The initial SHOW STACK command contains an address that SDA resolves
into an offset from the PAGE_MANAGEMENT module of the executive. The
READ command loads the corresponding symbols into the SDA symbol table
such that the reissue of the SHOW STACK command subsequently identifies
the same location as an offset within a specific page management routine.

SDA-62

SYSTEM DUMP ANALYZER
READ

SDA> READ/EXEC
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table
%SDA-I-READSYM, reading symbol table

SYS$COMMON: [SYS$LDR]RECOVERY_UNIT_SERVICES.EXE;1
SYS$COMMON: [SYS$LDR]RMS.EXE;1
SYS$COMMON: [SYS$LDR]CPULOA.EXE;1
SYS$COMMON: [SYS$LDR]LMF$GROUP_TABLE.EXE;1
SYS$COMMON: [SYS$LDR]SYSLICENSE.EXE;1
SYS$COMMON: [SYS$LDR]SYSGETSYI.EXE;1
SYS$COMMON: [SYS$LDR]SYSDEVICE.EXE;1
SYS$COMMON: [SYS$LDR]MESSAGE_ROUTINES.EXE;1
SYS$COMMON: [SYS$LDR]EXCEPTION.EXE;1
SYS$COMMON: [SYS$LDR]LOGICAL_NAMES.EXE;1
SYS$COMMON: [SYS$LDR]SECURITY.EXE;1
SYS$COMMON: [SYS$LDR]LOCKING.EXE;1
SYS$COMMON: [SYS$LDR]PAGE_MANAGEMENT.EXE;1
SYS$COMMON: [SYS$LDR]WORKING_SET_MANAGEMENT.EXE;1
SYS$COMMON: [SYS$LDR]IMAGE_MANAGEMENT.EXE;1
SYS$COMMON: [SYS$LDR]EVENT_FLAGS_AND_ASTS.EXE;1
SYS$COMMON: [SYS$LDR]IO_ROUTINES.EXE;1
SYS$COMMON: [SYS$LDR]PROCESS_MANAGEMENT.EXE;1
SYS$COMMON: [SYS$LDR]ERRORLOG.EXE;1
SYS$COMMON: [SYS$LDR]PRIMITIVE_IO.EXE;1
SYS$COMMON: [SYS$LDR]SYSTEM_SYNCHRONIZATION.EXE;1
SYS$COMMON: [SYS$LDR]SYSTEM_PRIMITIVES.EXE;1

This READ command brings all global symbols defined in the modules of
SYS$SYSTEM:SYS.EXE (as listed in Table SDA-5) into the SDA symbol
table. Included in its results is the work performed by the READ commands
illustrated in the two previous examples. The READ /EXECUTIVE command,
however, does not load those symbols contained in the tables described in
Table SDA-4.

SDA-63

SYSTEM DUMP ANALYZER
REPEAT

REPEAT
Repeats execution of the last command issued. On terminal devices, the
KPO key performs the same function as the REPEAT command.

FORMAT

REPEAT

PARAMETERS

None.

QUALIFIERS

None.

DESCRIPTION

The REPEAT command is useful for stepping through a linked list of data
structures, or for examining a sequence of memory locations.

EXAMPLES

SDA> FORMAT ©IOC$GL_DEVLIST
80008540 DDB$L_LINK
80008544 DDB$L_UCB
80008548 DDB$W_SIZE

80008554

DDB$B_NAME_LEN
DDB$T_NAME

SDA> FORMAT ©.
80008898 DDB$L_LINK
8000B89C DDB$L_UCB
8000B8AO DDB$W_SIZE

8000B8AC

DDB$B_NAME_LEN
DDB$T_NAME

SDA> IKPOI
8000BBEO DDB$L_LINK
8000BBE4 DDB$L_UCB
8000BBE8 DDB$W_SIZE

8000BBF4

DDB$B_NAME_LEN
DDB$T_NAME

80008898
8000B5EO
0044

03
11

0PA 11

8000BBEO
8000B9EO
0044

"MBA"
807F85CO
8000BC80
0044

"NLA"

This series of FORMAT commands pursues the chain of device data blocks
(DDBs) from the system global symbol IOC$GL_DEVLIST. The second
FORMAT command is constructed such that it refers to the contents of the

SDA-64

SYSTEM DUMP ANALYZER
REPEAT

address at the current location (see Section 5.2.4 for a discussion of SDA
symbols). Subsequently, pressing the KPO key-or issuing the REPEAT
command-is sufficient to display each DDB in the device list.

SDA> SHOW CALL_FRAME
Call Frame Information
Call Frame Generated by CALLG Instruction
7FFE7D78
7FFE7D7C
7FFE7D80
7FFE7D84

Condition Handler
SP Align Bits = 00
Saved AP
Saved FP

00000000
00000000
7FFE7DCO
7FFE7D94

CTL$GL_KSTKBAS+005CO
CTL$GL_KSTKBAS+00594

SDA> SHOW CALL_FRAME/NEXT_FP
Call Frame Information
Call Frame Generated by CALLS Instruction
Condition Handler
SP Align Bits = 00
Saved AP
Saved FP

7FFE7D94
7FFE7D98
7FFE7D9C
7FFE7DAO

00000000
20FCOOOO
7FFED024
7FFE7DE4

CTL$GL_KSTKBAS+005E4
SYSTEM_PRIMITIVES+020AA

SDA> REPEAT
Call Frame Information
Call Frame Generated by CALLG Instruction
Condition Handler

7FFE7DE4

00000000

The first SHOW CALL _FRAME displays the call frame indicated by the
current FP value. Because the /NEXT_FP qualifier to the instruction displays
the call frame indicated by the saved FP in the current call frame, you can
use the REPEAT command to repeat the SHOW CALL_FRAME/NEXT_FP
command and follow a chain of call frames.

SDA-65

SYSTEM DUMP ANALYZER
SEARCH

SEARCH
Scans a range of memory locations for all occurrences of a specified value.

FORMAT
PARAMETERS

[/qualifier} range[=}expression

range

Location in memory to be searched. A location can be represented by any
valid SDA expression (see Section 5.2). To search a range of locations, use
the following syntax:
m:n

Range of locations to be searched, from m to n

m;n

Range of locations to be searched, starting at m and continuing for n bytes

expression
Indication of the value for which SDA is to search. SDA evaluates the
expression and searches the specified range of memory for the resulting
value. For a description of SDA expressions, see Section 5.2.

QUALIFIERS

LONGWORD}
/LENGTH= { WORD
BYTE

Specifies the size of the expression value that the SEARCH command uses
for matching. If you do not specify the /LENGTH qualifier, the SEARCH
command uses a longword length by default.

/STEPS=

QUADWORD
LONGWORD
WORD
BYTE

Specifies the granularity of the search through the specified memory range.
After the SEARCH command has performed the comparison between the
value of expression and memory location, it adds the specified step factor to
the address of the memory location to determine the next location to undergo
the comparison. If you do not specify the /STEPS qualifier, the SEARCH
command uses a step factor of a longword.

DESCRIPTION

SDA-66

SEARCH displays each location as each value is found.

SYSTEM DUMP ANALYZER
SEARCH

EXAMPLES
iJ

SDA> SEARCH GB81F0;500 60068
Searching from 800B81FO to 800B86FO in LONGWORD steps for 00060068 ...
Match at 80088210
SDA>

The SEARCH command finds the value 0060068 in the longword at
800B8210.
~

SDA> SEARCH/STEPS=BYTE 80000000;1000 6
Searching from 80000000 to 80001000 in BYTE steps for 00000006 ...
Match at 80000A99
SDA>

The SEARCH command finds the value 00000006 in the longword at
80000A99.
~

SDA> SEARCH/LENGTH=WORD 80000000;2000 6
Searching from 80000000 to 80002000 in LONGWORD steps for 0006 ...
Match at 80000054
Match at 800001EC
Match at 800012AC
Match at 80001288
SDA>

The SEARCH command finds the value 0006 in the longword locations
80000054, 800001EC, 800012AC, and 800012B8.

SDA-67

SYSTEM DUMP ANALYZER
SET CPU

SET CPU
Selects a processor to become the SDA current CPU.

FORMAT
PARAMETER

SET CPU

cpu-id

cpu-id
Numeric value from 00 16 to 1F16 indicating the identity of the processor to be
made the current CPU. If you specify a value outside this range or a cpu-id of
a processor that was not active at the time of the system failure, SDA displays
the following message:
%SDA-E-CPUNOTVLD, CPU not booted or CPU number out of range

QUALIFIERS

None.

DESCRIPTION

When you invoke SDA to examine a system dump, the SDA current CPU
context defaults to that of the processor that caused the system to fail. When
analyzing a crash from a multiprocessing system, you may sometimes find it
useful to examine the context of another processor in the configuration.
The SET CPU command changes the current SDA CPU context to that of the
processor indicated by cpu-id. The CPU specified by this command becomes
the current CPU for SDA until you exit from SDA or change SDA CPU
context by issuing one of the following commands:
SET CPU cpu-id
SHOW CPU cpu-id
SHOW CRASH
The following commands also change SDA CPU context if the name or index
number (nn) refers to a current process.
SET PROCESS name
SET PROCESS /INDEX=nn
SHOW PROCESS name
SHOW PROCESS /INDEX=nn
Changing CPU context can cause an implicit change in process context under
the following circumstances:
•

If there is a current process on the CPU made current, SDA changes its

process context to that of that CPU's current process.
•

If there is no current process on the CPU made current, SDA process

context is undefined and no process-specific information is available until
you set SDA process context to that of a specific process.
See Section 4 for further discussion on the way in which SDA maintains its
context information.

SDA-68

SYSTEM DUMP ANALYZER
SET CPU

You cannot use the SET CPU command when examining the running system
with SDA.

EXAMPLE
$ANAL/CRASH SYS$SYSTEM:SYSDUMP.DMP
VAX/VMS System dump analyzer
Dump taken on 22-FEB-1989 14:22:17.66
NOBUFPCKT, Required buffer packet not present
SDA> SHOW CPU
CPU 01 Processor crash information
CPU 01 reason for Bugcheck: NOBUFPCKT, Required buffer packet not present

SDA> SHOW STACK
CPU 01 Processor stack
Current operating stack (INTERRUPT) :
80DAFB4C
80DAFB50

8018BC20
7FFC653E

SDA> SET CPU 00
SDA> SHOW CPU
CPU 00 Processor crash information
CPU 00 reason for Bugcheck: CPUEXIT, Shutdown requested by another CPU

SDA> SHOW STACK
CPU 00 Processor stack
Current operating stack (INTERRUPT):
8016ABD8
8016ABDC

00011F4C
00010F56

SDA> SHOW CRASH
System crash information
Time of system crash: 22-FEB-1989 14:22:17.66

SDA> SHOW STACK
CPU 01 Processor stack
Current operating stack (INTERRUPT):

SDA-69

SYSTEM DUMP ANALYZER
SET CPU

80DAFB4C
80DAFB50

8018BC20
7FFC653E

The series of SHOW CPU and SHOW STACK commands that occurs in this
example illustrates the switching of CPU context within an SDA session.
When SDA is first invoked, it is, by default, within the CPU context of the
processor that caused the crash (CPU 01). This is illustrated by the first set of
SHOW CPU and SHOW STACK commands.
The SET CPU 00 command explicitly changes SDA CPU context to that
of CPU 00, as illustrated by the second sequence of SHOW CPU and
SHOW STACK commands. Note that a SHOW CPU 00 command would
have the same effect as the two commands SET CPU 00 and SHOW CPU,
changing the SDA CPU context in addition to displaying the processorspecific information. Unlike the SHOW CPU cpu-id command, there is no
display associated with the SET CPU cpu-id command.
Lastly, the SHOW CRASH command resets the SDA CPU context to that of
the processor that caused the crash (CPU 01).

SDA-70

SYSTEM DUMP ANALYZER
SET LOG

SET LOG
Initiates or discontinues the recording of an SDA session in a text file.

FORMAT
PARAMETER

SET [NO]LOG

filespec

filespec
Name of the file in which you want SDA to log your commands and their
output. The default filespec is SYS$DISK:[defaulLdir]filename.LOG, where
SYS$DISK and [default-dir] represent the disk and directory specified in your
last SET DEFAULT command. You must specify a file name.

QUALIFIERS

None.

DESCRIPTION

The SET LOG command echoes the commands and output of an SDA session
to a log file. The SET NOLOG command terminates this behavior.
There are the following differences between the SET LOG command and the
SET OUTPUT command:
•

When logging is in effect, your commands and their results are still
displayed on your terminal. The SET OUTPUT command causes the
displays to be redirected to the output file such that they no longer
appear on the screen.

•

If an SDA command requires that you press RETURN to produce

successive screens of display, the log file produced by SET LOG will
record only those screens that are actually displayed. SET OUTPUT,
however, sends the entire output of all SDA commands to its listing file.
•

The SET LOG command produces a log file with a default file type of
LOG; the SET OUTPUT command produces a listing file whose default
file type is LIS.

•

The SET LOG command does not record output from the HELP command
in its log file. The SET OUTPUT command can record HELP output in its
listing file.

•

The SET LOG command does not record SDA error messages in its log
file. The SET OUTPUT command can record SDA error messages in its
listing file.

•

The SET OUTPUT command generates a table of contents, each item
of which refers to a display written to its listing file. SET OUTPUT also
produces running heads for each page of output. The SET LOG command
does not produce these items in its log file.

Note that, if you have used the SET OUTPUT command to redirect output to
a listing file, you cannot use a SET LOG command to direct the same output
to a log file.

SDA-71

SYSTEM DUMP ANALYZER
SET OUTPUT

SET OUTPUT
Redirects output from SDA to the specified file or device.

FORMAT
PARAMETER

SET OUTPUT

filespec

filespec
Name of the file to which SDA is to send the output generated by its
commands. The default filespec is SYS$DISK:[default_dir]filename.LIS, where
SYS$DISK and [default-dir] represent the disk and directory specified in your
last SET DEFAULT command. You must specify a file name.

DESCRIPTION

When you use the SET OUTPUT command to send the SDA output to a
file or device, SDA continues displaying the SDA commands that you enter
but sends the output generated by those commands to the file or device
you specify. (See the description of the SET LOG command for a list of
differences between it and the SET OUTPUT command.)
If you finish directing SDA commands to an output file and wish to return to

interactive display, issue the following command:
SDA> SET OUTPUT TT

If you use the SET OUTPUT command to send the SDA output to a listing
file, SDA builds a table of contents that identifies the displays you selected
and places the table of contents at the beginning of the output file. The SET
OUTPUT command formats the output into pages and produces a running
head at the top of each page.

SDA-72

SYSTEM DUMP ANALYZER
SET PROCESS

SET PROCESS
Selects a process to become the SDA current process.

FORMAT
SET PROCESS

PARAMETER

QUALIFIERS

process-name }
/INDEX=nn
{
/SYSTEM

process-name
Name of the process to become the SDA current process. The process-name
is a string containing up to 15 uppercase or lowercase characters; numerals,
the dollar sign ( $) character, and the underscore (-) character can also be
included in the string. If you include characters other than these, you must
enclose the entire string in quotation marks (fl fl).

/INDEX=nn
Specifies the process to be made current by its index into the system's list
of software process control blocks (PCBs). You can supply either of the
following values for nn:
•

The process index itself

•

The process identification (PID) or extended PID longword, from which
SDA extracts the correct index

To obtain these values for any given process, issue the SDA command SHOW
SUMMARY.

/SYSTEM
Specifies that the system process be made the SDA current process. Each
VMS system (uniprocessor or multiprocessor) uses a single system process
control block (PCB) and process header (PHD) as dummy structures, located
in system space, that record the system working set, global section table,
global page table, and other systemwide data.

DESCRIPTION

When you issue an SDA command such as an EXAMINE command, SDA
displays the contents of memory locations in its current process. To display
any information about another process, you must change the current process
with the SET PROCESS command.
When you invoke SDA to analyze a crash dump, its process context defaults
to that of the process that was current at the time of the crash. If the crash
occurred on a VMS multiprocessing system, SDA sets the CPU context to that
of the processor that crashed the system and the process context to that of the
process that was current on that processor.
When you invoke SDA to analyze a running system, its process context
defaults to that of the current process: that is, the one executing SDA.

SDA-73

SYSTEM DUMP ANALYZER
SET PROCESS

The SET PROCESS command changes the current SDA process context
to that of the process indicated by name or /INDEX=nn. The process
specified by this command becomes the current process for SDA until you
exit from SDA or change SDA process context by issuing one of the following
commands:
SET PROCESS /INDEX=nn
SET PROCESS process-name
SHOW PROCESS /INDEX=nn
In the analysis of a crash dump from a multiprocessing system, changing
process context can involve a switch of CPU context as well. For instance, if
you issue a SET PROCESS command for a process that is current on another
CPU, SDA will automatically change its CPU context to that of the CPU on
which that process is current. The following commands can have this effect if
process-name or index number (nn) refers to a current process.
SET PROCESS process-name
SET PROCESS /INDEX=nn
SHOW PROCESS process-name
SHOW PROCESS /INDEX=nn
See Section 4 for further discussion on the way in which SDA maintains its
context information.

EXAMPLES

SDA> SHOW PROCESS
Process index: 0012
Process status:

Name: NETACP

00149001

PCB address
PHD address

Extended PID: 28C00092

RES,WAKEPEN,NOACNT,PHDRES,LOGIN
800F1140
80477200

JIB address
Swapf ile disk address

801FDAOO
01000F01

SDA> SHOW SUMMARY
Current process summary
PHO
Wkset
Extended Indx Process name
Username
State Pri
PCB
-------- --------- PIO -- ---- --------------- ---- ----·- -COM
0 80002100 80001F88
0
28C00080 0000 NULL
16 800023C8 80002250
0
28C00081 0001 SWAPPER
HIB
MWAIT 6 8010FEAO 803F8600
323
28C00483 0003 KLINGON
KLINGON
10 800B5A10 80610AOO
69
SYSTEM
COM
28C00085 0005 ERRFMT
71
LEF
7 800C7000 80227AOO
28C00087 0007 OPCOM
SYSTEM

SDA-74

SYSTEM DUMP ANALYZER
SET PROCESS

SDA> SET PROCESS ERRFMT
SDA> SHOW PROCESS
Process index: 0005
Name: ERRFMT
Process status:
PCB address

00040001

Extended PID: 28C00085

RES,PHDRES
800B5A10

JIB address

801E5COO

The first SHOW PROCESS command shows the current process to be
NETACP. The SHOW SUMMARY command shows the names of the other
processes that exist. The SET PROCESS command sets the current process
to ERRFMT, as shown by the second SHOW PROCESS command. Note
that the SET PROCESS command could also have been issued as one of the
following:
SDA>

SET PROCESS/INDEX=5

SDA>

SET PROCESS/INDEX=801E5COO

SDA-75

SYSTEM DUMP ANALYZER
SET RMS

SET RMS
Changes the options shown by the SHOW PROCESS/RMS command.

FORMAT
PARAMETER

SET RMS =(option{, ... })

option
Data structure or other information to be displayed by the SHOW
PROCESS/RMS command. Table SDA-6 lists those keywords that may be
used as options. The default option is option=ALL:ALL,NOPIO, designating
for display by the SHOW PROCESS /RMS command all structures for all files
related to the process's image 1/0.
To list more than one option, enclose the list in parentheses and separate
options by commas. You can add a given data structure to those displayed by
ensuring that the list of keywords begins with the * ( asterisk) symbol. You
can delete a given data structure from the current display by preceding its
keyword with "NO".

QUALIFIERS

None.

DESCRIPTION

The SET RMS command determines the data structures to be displayed
by the SHOW PROCESS /RMS command. (See the examples included in
the discussion of the SHOW PROCESS command for an indication of the
information provided by various displays.) You can examine the options that
are currently selected by issuing a SHOW RMS command.
Table SDA-6

SET RMS Command Keywords for Displaying Process
RMS Information

Keyword

Meaning

[NO]ALL[: ifi] 1

All control blocks (default)

[NO]ASB

Asynchronous context block

[NO]BDB

Buffer descriptor block

[NO]BDBSUM

BOB summary page

[NO]BLB

Buff er lock block

[NO]BLBSUM

Buffer lock summary page

[NO]CCB

Channel control block

[NO]DRC

Directory cache

[NO]FAB

File attributes block

[NO]FCB

File control block

1 The optional parameter ifi is an internal file identification. The default ifi (ALL) is all the
files the current process has opened.

SDA-76

SYSTEM DUMP ANALYZER
SET RMS

Table SDA-6 (Cont.)
Keyword

SET RMS Command Keywords for Displaying
Process RMS Information

Meaning

[NO]FWA

File work area

[NO]GBDSUM

GBD summary page

[NO]GBSB

Global buffer synchronization block

[NO]GBD

Global buffer descriptor

[NO]GBH

Global buffer header

[NO]IDX

Index descriptor

[NO]IFAB[:ifi]
[NO]IFB[:ifi]

Internal FAB
Internal FAB

[NO]IRAB

Internal RAB

[NO]IRB

Internal RAB

[NO]JFB

Journaling file block

[NO]NAM

Name block

[NO]NWA

Network work area

[NO]PIO

Image 1/0 (NOPIO), the default, or process 1/0 (Pl0) 2

[NO]RAB

Record attributes block

[NO]RLB

Record lock block

[NO]RU

Recovery unit structures, including the recovery unit block
(RUB), recovery unit stream block (RUSB), and recovery unit
file block (RUFB)

[NO]SFSB

Shared file synchronization block

[NO]WCB

Window control block

[NO]XAB

Extended attribute block

[NO]*

Current list of options displayed by the SHOW RMS command

1The optional parameter ifi is an internal file identification. The default ifi (ALL) is all the
files the current process has opened.

2 Specifying the PIO option causes the SHOW PROCESS/RMS command to display the

indicated structures for process-permanent file 1/0.

EXAMPLES

D SDA> SHOW RMS

RMS Display Options: IFB,IRB,IDX,BDB,BDBSUM,ASB,CCB,WCB,FCB,FAB,RAB,NAM,XAB,RLB,
BLB,BLBSUM,GBD,GBH,FWA,GBDSUM,JFB,NWA,RU,DRC,SFSB,GBSB

Display RMS structures for all IFI values.
SDA>
SDA>

SET RMS=IFB
SHOW RMS

RMS Display Options:

IFB

Display RMS structures for all IFI values.

SDA-77

SYSTEM DUMP ANALYZER
SET RMS

The first SHOW RMS command shows the default selection of data structures
that are displayed in response to a SHOW PROCESS /RMS command. The
SET RMS command selects only the IFB to be displayed by subsequent
SET /PROCESS commands.
~

SDA> SET RMS=(*,BLB,BLBSUM,RLB)
SDA> SHOW RMS
RMS Display Options:

IFB,RLB,BLB,BLBSUM

Display RMS structures for all IFI values.

The SET RMS command adds the BLB, BLBSUM, and RLB to the list of data
structures currently displayed by the SHOW PROCESS /RMS command.
=:J

SDA> SET RMS=(*,NORLB,IFB:05)
SDA> SHOW RMS
RMS Display Options: IFB,BLB,BLBSUM
Display RMS structures only for IFI=5.

The SET RMS command removes the RLB from those data structures
displayed by the SHOW PROCESS /RMS command and causes only
information about the file with the ifi of 5 to be displayed.
~

SDA> SET RMS=(*,PIO)

The SET RMS command indicates that the data structures designated for
display by SHOW PROCESS/RMS be associated with process-permanent 1/0
instead of image 1/0.

SDA-78

SYSTEM DUMP ANALYZER
SHOW CALL_FRAME

SHOW CALL_FRAME
Displays the locations and contents of the longwords representing a
procedure call frame.

FORMAT

PARAMETER

SHOW CALL_FRAME

starting-address ]
[ /NEXT_FP

starting-address
Expression representing the starting address of the procedure call frame to be
displayed. The default starting-address is the longword contained in the FP
register of the SDA current process.

QUALIFIER

/NEXT_FP
Displays the procedure call frame starting at the address stored in the FP
longword of the last call frame displayed by this command. You must have
issued a SHOW CALL _FRAME command previously in the current SDA
session in order to use the /NEXT_FP qualifier to the command.

DESCRIPTION

Whenever a procedure is called using CALLG or CALLS instructions,
information is stored on the stack of the calling routine in the form of a
procedure call frame. Figure SDA-5 illustrates the format of a call frame.7
The SHOW CALL _FRAME command interprets the contents of the
designated call frame and displays whether the call frame was generated
by a CALLG or CALLS instruction. If it locates nonzero bits in the portion
of the second longword that represents the upper byte of the processor status
word (PSW), it presents a message that indicates the fault or trap in effect.
For example:
Nonzero PSW Bits (15:8) => Reserved Operand Fault on RET

SHOW_CALL _FRAME then produces four columns of information:

The components of the call frame.

The virtual addresses that are part of the call frame.

The contents of the longwords at these addresses.

A symbolic representation of the contents of each longword, if possible.
SDA does not attempt to symbolize the second longword in the call frame
(mask-PSW longword), which contains the register save mask and the
processor status word (PSW).

In Figure SDA-5, the second longword contains the stack pointer alignment (SPA) bits, which indicate the 0
to 3 bytes needed to align the frame to a longword boundary. The S bit is set if the frame resulted from a
CALLS instruction; clear if it resulted from a CALLG inst.ruction.

SDA-79

SYSTEM DUMP ANALYZER
SHOW CALL_FRAME

Figure SDA-5 Call Frame

condition handler address

SPA}

s} oJ mask< 11 :O> lsaved PSW < 15:5>1 0

:(FP)

saved AP
saved FP
saved PC
saved RO

saved R11
ZK-6564-HC

The SHOW CALL _FRAME command follows this listing with an indication
of how many bytes were used to align the call frame to a longword boundary.
For call frames generated by a CALLS instruction, the SHOW CALL _FRAME
instruction displays the argument list to the call frame in three columns
containing the virtual address of each item, its contents, and symbolic
representation.
All valid procedure call frames begin on a longword boundary. If the
specified address expression does not begin on a longword boundary, the
call frame is invalid and the SDA displays the following message:
Invalid Call Frame:

Start Address Not On Longword Boundary

If you attempt to format an address that is not a call frame or is an invalid
call frame (that is, bit 28 of the second longword is not zero), SDA displays
the following message:
Invalid Call Frame:

Bit 28 is Set in "Mask-PSW" Longword

When using the SHOW CALL_FRAME/NEXT_FP command to follow a
chain of call frames, SDA signals the end of the chain by the message
%SDA-E-NOTINPHYS, 00000000 : not in physical memory

This message indicates that the saved FP in the previous call frame has a zero
value.

SDA-80

SYSTEM DUMP ANALYZER
SHOW CALL_FRAME

EXAMPLE
SDA> SHOW CALL_FRAME
Call Frame Information
Call Frame Generated by CALLG Instruction
Condition Handler
7FFE7D78
SP Align Bits = 00
7FFE7D7C
Saved AP
7FFE7D80
Saved FP
7FFE7D84
Return PC
7FFE7D88
Align Stack by 0 Bytes =>
SDA> SHOW CALL_FRAME/NEXT_FP
Call Frame Information

00000000
00000000
7FFE7DCO
7FFE7D94
8015303F

CTL$GL_KSTKBAS+005CO
CTL$GL_KSTKBAS+00594
EXCEPTION+0043F

Call Frame Generated by CALLS Instruction
Condition Handler
7FFE7D94 00000000
SP Align Bits = 00
7FFE7D98 20FCOOOO
Saved AP
7FFE7D9C 7FFED024
Saved FP
7FFE7DAO 7FFE7DE4
Return PC
7FFE7DA4 801D58AA
R2
7FFE7DA8 7FFE7DDO
7FFE7DAC 7FFDB9F8
R3
R4
7FFE7DBO 8026C720
7FFE7DB4 7FFDBAOO
R5
7FFE7DB8 7FFE6300
R6
7FFE7DBC 00000003
R7
Align Stack by 0 Bytes =>
Argument List
7FFE7DCO 00000003
7FFE7DC4 7FFE7DDO
7FFE7DC8 00000000
7FFE7DCC 00000000
SDA> SHOW CALL_FRAME/NEXT_FP
Call Frame Information

CTL$GL_KSTKBAS+005E4
MMG$IMGRESET+00066
CTL$GL_KSTKBAS+005DO

CTL$A_DISPVEC+00500

CTL$GL_KSTKBAS+005DO

Call Frame Generated by CALLG Instruction
Condition Handler
7FFE7DE4 00000000
SP Align Bits = 00
7FFE7DE8 00000000
Saved AP
7FFE7DEC 7FFED024
Saved FP
7FFE7DFO 7FFECFF8
Return PC
7FFE7DF4 8015303F
Align Stack by O Bytes =>

EXCEPTION+0043F

The SHOW CALL _FRAME commands in this SDA session follow a chain of
call frames from that specified in the FP of the SDA current process.

SDA-81

SYSTEM DUMP ANALYZER
SHOW CLUSTER

SHOW CLUSTER
Displays information for all the nodes in a V AXcluster or a specific node in
a V AXcluster from the viewpoint of the connection manager or from that
of the system communications services (SCS).

FORMAT

SHOW CLUSTER

PARAMETERS

None.

QUALIFIERS

/CSID=csid

/CS/D=csid }
{ /SCS

Displays VAXcluster information for a specific VAXcluster member node. The
value csid is the cluster system identification number (CSID) of the node to
be displayed. 8

/SCS
Displays a view of the VAXcluster as seen by SCS.

DESCRIPTION

By default, the SHOW CLUSTER command provides a view of the VAXcluster
from the perspective of the connection manager. When you use the /SCS
qualifier, however, SHOW CLUSTER provides a view of the cluster from the
perspective of the port driver or drivers.
VAXcluster as Seen by the Connection Manager

The SHOW CLUSTER command provides a series of displays.
The V AXcluster summary display supplies the following information:
•

Number of votes required for a quorum

•

Number of votes currently available

•

Number of votes allocated to the quorum disk

•

Status summary indicating whether or not a quorum is present

The CSB list displays information about the VAXcluster system blocks
(CSB) currently in operation; there is one CSB assigned to each node of the
VAXcluster. For each CSB, the CSB list displays the following information:

•

Its address

•

Name of the VAXcluster node it describes

•

CSID associated with the node

You can find the CSID for a specific node in a VAXcluster by examining the CSB list display of the SHOW
CLUSTER command. Other SDA displays refer to a system's CSID. For instance, the SHOW LOCK command
indicates where a lock is mastered or held by CSID.

SDA-82

SYSTEM DUMP ANALYZER
SHOW CLUSTER

•

Number of votes (if any) provided by the node

•

Its state 9

•

Its status9

The cluster block display includes information recorded in the cluster
block (CLUB), including a list of activated flags, a summary of quorum
and vote information, and other data that applies to the VAXcluster from the
perspective of the node for which the SDA is being run.
The cluster failover control block display provides detailed information
concerning the cluster failover control block (CLUFCB), and the cluster
quorum disk control block display provides detailed information from the
cluster quorum disk control block (CLUDCB).
Subsequent displays provide information for each CSB listed previously in the
CSB list display. Each display shows the state and flags of a CSB, as well as
other specific node information. (See the VMS Show Cluster Utility Manual for
information about the flags for VAXcluster nodes.)
VAXcluster as Seen by the Port Driver

The SHOW CLUSTER/SCS command provides a series of displays.
The SCS listening process directory lists those processes that are listening
for incoming SCS connect requests. For each of these processes, this display
records the following information:
•

Address of its directory entry

•

Connection ID

•

Name

•

Explanatory information, if available

The SCS systems summary display provides the system block (SB) address,
node name, system type, system ID, and the number of connection paths for
each SCS system. An SCS system can be a VAXcluster member, HSC, UDA,
or other such device.
Subsequent displays provide detailed information for each of the system
blocks and the associated path blocks. The system block displays include the
maximum message and datagram sizes, local hardware and software data,
and SCS poller information. Path block displays include information that
describes the connection, including remote functions and other path-related
data.

For information about the state and status of nodes, see the description of the ADD command in the VMS

Show Cluster Utility Manual.

SDA-83

SYSTEM DUMP ANALYZER
SHOW CLUSTER

EXAMPLES

SDA> SHOW CLUSTER

VAXcluster data structures
--- VAXcluster Summary --Quorum

Votes

Quorum Disk Votes

Status Summary
quorum

CSB list
Address

Node

CSID

803686FO
80368550
80367B90

SOLLY
GUS
DORIS

000100C8
000100C9
000100C5

Votes

State

1
1
1

open
open
open

Status

member,qf_active
member,qf_active
member,qf_active

--- Cluster Block (CLUB) 801C3F70 --Flags: 10080001 cluster,init,quorum
Quorum/Votes
Quorum Disk Votes
Nodes
Quorum Disk
Found Node SYSID
Founding Time

2/3
1
3
$255$DUA2
0000000008AO
3-DEC-1988
00:01:44
Index of next CSID
OOD2
Quorum Disk Cntrl Block 80334EOO
Timer Entry Address
00000000
CSP Queue
empty

Last transaction code
02
Last trans. number
1126
Last coordinator CSID
00000000
Last time stamp
26-MAR-1986
18:52:32
Largest trans. id
00000466
Resource Alloc. retry
0
Figure of Merit
00000000
Member State Seq. Num
0190
Foreign Cluster
00000000

--- Cluster Failover Control Block (CLUFCB) 801C407C --Flags: 00000000
Failover Step Index
Failover Instance ID

00000028
00000466

CSB of Synchr. System

803686FO

--- Cluster Quorum Disk Control Block (CLUDCB) 80334EOO --State: 0001 qs_not_ready
Flags: 0000
Iteration Counter
Activity Counter
Quorum file LBN

0
0

00000000

UCB address
TQE address
IRP address

--- SOLLY Cluster System Block (CSB) 803686FO --State: 01 open
Flags: 02020302 member,cluster,qf_active,selected,status_rcvd

SDA-84

00000000
80419F40
803665AO

SYSTEM DUMP ANALYZER
SHOW CLUSTER

Quorum/Votes
2/1
Quor. Disk Vote
1
CSID
000100C8
Eco/Version
0/12
Reconn. time 00000059
Ref. count
2
Ref. time 18-DEC-1988
08:53:58

Next seq. number
0247
Last seq num rcvd
0314
Last ack. seq num
0247
Unacked messages
1
Ack limit
4
Incarnation 18-DEC-1988
08:52:20
Lock mgr dir wgt
1

Send queue
Resend queue
Block xfer Q.
CDT address
PDT address
TQE address
SB address
Current CDRP

00000000
00000000
empty
801C28FO
801CEA20
00000000
8041B6EO
00000000

The preceding example shows the screen displays for the SHOW CLUSTER
command. (Displays for nodes GUS and DORIS, similar to that for node
SOLLY, are also included in the SHOW CLUSTER output but have been
omitted from the preceding example.)
~

SDA> SHOW CLUSTER /CSID=000100C8

VAXcluster data structures
--- SOLLY Cluster System Block (CSB) 803686FO --State: 01 open
Flags: 02020302 member,cluster,qf_active,selected,status_rcvd
Quorum/Votes
2/1
Quor. Disk Vote
1
CSID
000100C8
Eco/Version
0/12
Reconn. time 00000059
Ref. count
2
Ref. time 18-DEC-1988
08:53:58

Next seq. number
0247
Last seq num rcvd
0314
Last ack. seq num
0247
Unacked messages
1
Ack limit
4
Incarnation 18-DEC-1988
08:52:20
Lock mgr dir wgt
1

Send queue
Resend queue
Block xfer Q.
CDT address
PDT address
TQE address
SB address
Current CDRP

00000000
00000000
empty
801C28FO
801CEA20
00000000
8041B6EO
00000000

The preceding example shows the use of the /CSID qualifier to obtain
information about a specific node (in this instance, node SOLLY). The
information displayed is identical to that shown for the specified node in
the SHOW CLUSTER command.
~

SDA> SHOW CLUSTER /SCS

VAXcluster data structures
--- SCS Listening Process Directory
Entry Address

Connection ID

Process Name

80419D60
80419E20

08EEOOOO
08EE0001

SCS$D IRECTORY
VMS$VAXcluster

Information

SCS Systems Summary --SB Address

Node

Type

System ID

Paths

PINTO
DORIS
GUS
SOLLY
DODGER

HSC
VMS
VMS
VMS
HSC

OOOOOOOOF10E
0000000008A9
0000000008A1
0000000008AO
OOOOOOOOFOOF

1
1
1
1
1

---------8041A120
8041AA20
8041AB40
8041B6EO
80410420

---------

SDA-85

SYSTEM DUMP ANALYZER
SHOW CLUSTER

--- PINTO System Block (SB) 8041A120 --OOOOOOOOF10E
System ID
Max message size
66
Max datagram size
62
Local hardware type
HS50
Local hardware vers. 022702220222
022202220222

Local software type
Local software vers.
Local software incarn.
SCS poller timeout
SCS poller enable mask

HSC
X301
8355FEOO
008DA59A
OOOF
01

--- Path Block (PB) 8041C400 --Status:

0000

Remote sta. addr.
OOOOOOOOOOOE
Remote state
OOOOOOOOOOOE
Remote hardware rev.
00000225
Remote func. mask
4F710200
OE
Resetting port
1
Handshake retry cnt.
Msg. buf. wait queue
empty

Remote port type
Number of data paths
Cables state
Local state
Port dev. name
SCS MSGBUF address
PDT address

HSC
2

A-OK B-OK
OPEN
PABO
80390270
801CEA20

--- DORIS System Block (SB) 8041AA20
0000000008A9
System ID
Max message size
112
Max datagram size
576
Local hardware type
V780
Local hardware vers. 010E0138207A
000030030E10

Local software type
Local software vers.
Local software incarn.

VMS
V5.0
A9D31760
008DA59B

SCS poller timeout
SCS poller enable mask

oooc
00

Path Block (PB) 80437E80 --Status:

0000

Remote sta. addr.
000000000002
ENAB
Remote state
Remote hardware rev.
00040003
Remote func. mask
FFFFFFOO
02
Resetting port
Handshake retry cnt.
1
Msg. buf. wait queue
empty

Remote port type
Number of data paths
Cables state
Local state
Port dev. name
SCS MSGBUF address
PDT address

CI780
2

A-OK B-OK
OPEN
PABO
8036FOBO
801CEA20

The preceding example shows a subset of a typical output for the SHOW
CLUSTER/SCS command. In this system, there are three VMS nodes
(DORIS, GUS, and SOLLY), and there are two HSCs (PINTO and DODGER).
After the summary information in the first two screen displays, specific
information for each system block and its associated path block is shown.

SDA-86

SYSTEM DUMP ANALYZER
SHOW CONNECTIONS

SHOW CONNECTIONS
Displays information about all active connections between systems
communications services (SCS) processes or a single connection.

FORMAT

SHOW CONNECTIONS [/ADDRESS=cdt-addressj

PARAMETERS

None.

QUALIFIER

/ADDRESS=cdt-address
Displays information contained in the connection descriptor table (CDT) for a
specific connection. 10

DESCRIPTION

The SHOW CONNECTIONS command provides a series of displays.
The CDT summary page lists information regarding each connection on the
local system, including the following:
•

CDT address

•

Name of the local process with which the CDT is associated

•

Connection ID

•

Current state

•

Name of the remote node (if any) to which it is currently connected

The CDT summary page concludes with a count of CDTs that are free and
available to the system.
SHOW CONNECTIONS next displays a page of detailed information for each
active CDT listed previously.

You can find the cdt-address for any active connection on the system in the CDT summary page display of
the SHOW CONNECTIONS command. In addition, CDT addresses are also stored in many individual data
structures related to SCS connections. These data structures include class driver request packets (CDRPs) and
unit control blocks (UCBs) for class drivers that use SCS and cluster system blocks (CSBs) for the connection
manager.

SDA-87

SYSTEM DUMP ANALYZER
SHOW CONNECTIONS

EXAMPLES
iJ

SDA> SHOW CONNECTIONS
VAXcluster data structures
--- CDT Summary Page --CDT Address

Local Process

801C2670
801C2710
801C27BO
801C2850
801C28FO
801C2990

SCS$DIRECTORY
VMS$VAXcluster
VMS$VAXcluster
VMS$DISK_CL_DRVR
VMS$VAXcluster
VMS$VAXcluster

Number of free CDTs:

Connection ID

State

Remote Node

08EEOOOO
08EE0001
08FF0002
08FD0003
08EF0004
08F00005

listen
listen
open
open
open
open

DORIS
PINTO
SOLLY
GUS

--- Connection Descriptor Table (CDT) 801C2670 --State: 0001 listen
Blocked State: 0000
Local Con. ID
08EEOOOO
Remote Con. ID 78A30017
Receive Credit
0
Send Credit
1
Min. Rec. Credit
0
Pend Rec. Credit
0
Initial Rec. Credit
0
oooooooooooc
Rem. Sta.
Rej/Disconn Reason
0
Queued for BDT
0
Queued Send Credit
0

Local Process:

Datagrams sent
Datagrams rcvd
Datagram discard
Messages Sent
Messages Revd.
Send Data !nit.
Req Data Init.
Bytes Sent
Bytes rcvd
Total bytes map

SCS$D !RECTORY

0
0
0
0
0
0
0
0
0
0

Message queue
Send Credit Q.
PB address
PDT address
Error Notify
Receive Buffer
Connect Data
Aux. Structure

empty
empty
80438300
801CEA20
8022B816
00000000
00000000
00000000

The preceding example shows the CDT summary page, and the first page of
the detailed displays for each CDT.
~

SDA> SHOW CONNECTIONS /ADDRESS=801C27BO
VAXcluster data structures
--- Connection Descriptor Table (CDT) 801C27BO --State: 0002 open
Blocked State: 0000

Local Process:
Remote Node: :Process:

VMS$VAXcluster
DORIS: :VMS$VAXcluster

Local Con. ID
08FF0002
Remote Con. ID 33440003
Receive Credit
4
Send Credit
5
Min. Rec. Credit
0
Pend Rec. Credit
1
Initial Rec. Credit
5
Rem. Sta.
000000000002
Rej/Disconn Reason
0
Queued for BDT
0
Queued Send Credit
0

Datagrams sent
0
Datagrams rcvd
0
Datagram discard
0
Messages Sent
267
Messages Revd.
289
Send Data Init.
0
Req Data !nit.
0
Bytes Sent
0
Bytes rcvd
0
Total bytes map
0

Message queue
Send Credit Q.
PB address
PDT address
Error Notify
Receive Buffer
Connect Data
Aux. Structure

empty
empty
80437E80
801CEA20
80227950
8039AF80
80367COC
80367B90

The preceding example shows the use of the /ADDRESS qualifier to obtain
information about a specific connection.

SDA-88

SYSTEM DUMP ANALYZER
SHOW CPU

SHOW CPU
Displays information about the state of a processor at the time of the
system failure.

FORMAT
PARAMETER

SHOW CPU

[cpu-id]

cpu-id
Numeric value from 00 to 1F16 indicating the identity of the processor for
which context information is to be displayed. If you specify a value outside
this range or the cpu-id of a processor that was not active at the time of the
system failure, SDA displays the following message:
%SDA-E-CPUNOTVLD, CPU not booted or CPU number out of range

If you use the cpu-id parameter, the SHOW CPU command performs an
implicit SET CPU command, making the processor indicated by cpu-id the
current CPU for subsequent SDA commands. (See the description of the SET
CPU command and Section 4 for information on how this can affect the CPU
context-and process context-in which SDA commands execute.)

QUALIFIERS

None.

DESCRIPTION

The SHOW CPU command displays crash information about the processor
specified by cpu-id or, by default, the SDA current CPU, as defined in
Section 4. You cannot use the SHOW CPU command when examining the
running system with SDA.
The SHOW CPU command produces several displays. First, there is a brief
description of the crash and its environment that includes the following:
•

Reason for the bugcheck

•

Name of the currently executing process. If no process has been
scheduled on this processor, SDA displays the following message:

Process currently executing: no processes currently scheduled on the processor

•

File specification of the image executing within the current process (if
there is a current process)

•

Interrupt priority level (IPL) of the processor at the time of the system
failure

Next, the general registers display shows the contents of the processor's
general purpose registers (RO through Rl 1), the AP, FP, SP, PC, and PSL at
the time of the crash.

SDA-89

SYSTEM DUMP ANALYZER
SHOW CPU

The processor registers display consists of the following three parts:
•

Common processor registers

•

Processor-specific registers

•

Stack pointers and memory interconnect silos

The first section includes registers, common to all VAX processors, that are
used by VMS to maintain the current process's virtual address space, system
space, or other system functions. The following registers are among those
displayed:
•

Program region (PO space) base register (POBR)

•

Program region length register (POLR)

•

Control region (Pl space) base register (PlBR)

•

Control region length register (PlLR)

•

System region (SO space) base register (SBR)

•

System region length register (SLR)

•

Process control block base register (PCBB)

•

System control block base register (SCBB)

•

Asynchronous system trap level (ASTLVL)

•

Software interrupt summary register (SISR)

•

Internal clock control/status register (ICCS)

•

System identification register (SID)

The second section of the processor registers display shows those registers
that are specific to the type of VAX processor being examined. (The SHOW
CRASH command displays the processor type.) The contents of the register
display vary according to the type of processor involved in the crash and are
used primarily in hardware diagnostics.
The final section of the display includes the five stack pointers: the interrupt
stack pointer (ISP) and the four pointers of the kernel, executive, supervisor,
and user stacks (KSP, ESP, SSP, and USP, respectively). Certain processors,
such as the VAX 8800 and VAX 8600, also display the contents of the silos of
their memory interconnects in this section.
The SHOW CPU command concludes with a listing of the spin locks, if
any, owned by the processor at the time of the crash, reproducing some of
the information given by the SHOW SPINLOCKS command. The spin lock
display includes the following information:

SDA-90

•

Name of the spin lock

•

Address of the spin lock data structure (SPL)

•

IPL and rank of the spin lock

•

Number of processors waiting for this processor to release the spin lock

SYSTEM DUMP ANALYZER
SHOW CPU

•

Indication of the depth of this processor's ownership of the spin lock. A
number greater than 1 indicates that this processor has nested acquisitions
of the spin lock.

EXAMPLE
SDA> SHOW CPU
CPU 00 Processor crash information

CPU 00 reason for Bugcheck: INVEXCEPTN, Exception while above ASTDEL or on interrupt stack
Process currently executing: NETACP
Current image file: $254$DUA200: [SYS6.SYSCOMMON.]<SYSEXE>NETACP.EXE;3
Current IPL: 8

(decimal)

General registers:
RO = 00000008
R4 = 00000002
R8 = 00000000
AP = OOOOBE34
PSL = 00080009

R1
R5
R9
FP

= 00080000

= 8047FC40
= 00000062
= 7FFE7DDO

R2 = 8047FC40
R6 = 00000036
R10 = 7FFE7D70
SP = 7FFE7D30

R3 = 000003AC
R7 = 00000000
R11 = 0000747C
PC = 80146682

Processor registers:
POBR
POLR
P1BR
P1LR

= 816EB600
= ooooococ
= 80FFCEOO
= 001FFC5F

SBR
SLR
PCBB
SCBB

= 01A6A800
= 00065600
= 008AF2AO
= 01A62600

ASTLVL = 00000004
SISR
= 00000000
recs = 00000041
SID
= 067F014F

ICR
TODR
COR

= FFFFEDEA
= 2B914COF
= 00000001

REVR1 = 11121111
REVR2 = FFOOFF12
CPUINFO= 000009F7

NMIFSR = OOOCOOOO
NMIEAR = 2243F830

ISP
KSP
ESP
SSP
USP

= 8016ACOO
= 7FFE7D30
= 7FFE9EOO
= 7FFEDEOO
= 7FF8E590

NMI bus silo:
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

SDA-91

SYSTEM DUMP ANALYZER
SHOW CPU

Spinlocks currently owned by CPU 00
IOLOCK8
Owner CPU ID
Ownership Depth
CPUs Waiting

Address
IPL
Rank
Index

00
0001
0000

SDA> EXAMINE R5
11
R5: 8047FC40
©G. II
SDA> SHOW PROCESS
Process index: OOOD
Name: NETACP
Process status:

00148001

80185E50
08
14
34

Extended PID: 33C0010D

RES,NOACNT,PHDRES,LOGIN

SDA> SHOW CPU 01
CPU 01 Processor crash information

CPU 01 reason for Bugcheck: CPUEXIT, Shutdown requested by another CPU
Process currently executing: no processes currently scheduled on this CPU
Current IPL: 31

(decimal)

No spinlocks currently owned by CPU 01
SDA> EXAMINE R5
R5 : 83ED5EOO
II
~ II
SDA> SHOW PROCESS
%SDA-E-BADPROC, no such process

This SDA session illustrates the output of the SHOW CPU command in the
analysis of a crash dump from a VAX 8800 multiprocessing system with
two active processors. The first SHOW CPU command displays the crash
information particular to CPU 00, which initially posted an INVEXCEPTN
bugcheck from within process NETACP and then requested CPU 01 to take
a bugcheck (CPUEXIT) as well. That the crash occurred at IPL 8 signifies,
perhaps, that a driver fork process is involved.
The second instance of the SHOW CPU command (SHOW CPU 01)
corroborates that CPU 01 was requested to crash by CPU 00.
Significantly, the second SHOW CPU command changes both the SDA
current CPU context and current process context. The two EXAMINE RS
commands are executed under different CPU contexts as the values they
produce differ. In the CPU context of CPU 00, the current process context is
that of process NETACP. There is no current process on CPU 01; thus, SDA
process context is initially undefined when its CPU context is changed to that
of CPU 01.

SDA-92

SYSTEM DUMP ANALYZER
SHOW CRASH

SHOW CRASH
In the analysis of a system failure, displays information about the state of
the system at the time of the failure. In the analysis of a running system,
provides information identifying the system.

FORMAT

SHOW CRASH

PARAMETERS

None.

QUALIFIERS

None.

DESCRIPTION

The SHOW CRASH command has two different manifestations, depending
upon whether it is issued within the analysis of a running system or within
the analysis of a system failure.
In either case, if the SDA current CPU context is not that of the processor that
signaled the bugcheck, the SHOW CRASH command performs an implicit
SET CPU command to make that processor the SDA current CPU. (See the
description of the SET CPU command and Section 4 for a discussion of
how this can affect the CPU context-and process context-in which SDA
commands execute.)
When used during the analysis of a running system, the SHOW CRASH
command produces a display that describes the system and the version of
VMS that it is running. The system crash information display contains the
following information:
•

Date and time that the ANALYZE/SYSTEM command was issued
(entitled "Time of system crash" in the display)

•

Name and version number of the operating system

•

Major and minor IDs of the operating system

•

Identity of the VAX system, including an indication of its VAXcluster
membership

•

CPU ID of the primary CPU

•

Two bit masks indicating which processors in the system are active and
which are available for booting, respectively

When used during the analysis of a system failure, the SHOW CRASH
command produces several displays that identify the system and describe its
state at the time of the failure.
The system crash information display in this context provides the following
information:
•

Date and time of the system crash.

•

Name and version number of the operating system.

SDA-93

SYSTEM DUMP ANALYZER
SHOW CRASH

•

Major and minor IDs of the operating system.

•

Identity of the VAX system, including an indication of its VAXcluster
membership and the location of the primary CPU in a multiprocessing
configuration.

•

CPU IDs of both the primary CPU and the CPU that initiated the
bugcheck. In a VAX uniprocessor system, these IDs are identical.

•

Two bit masks indicating which processors in the system are active and
which are available for booting, respectively.

•

For each active processor in the system, the name of the bugcheck that
caused the failure. Generally, there will be only one significant bugcheck
in the system. All other processors typically display the following as their
reason for taking a bugcheck:
CPUEXIT, Shutdown requested by another CPU

Subsequent screens of the SHOW CRASH command display information
about the state of each active processor on the system at the time of the
system failure. The information in these screens is identical to that produced
by the SHOW CPU command, including the general purpose registers,
processor-specific registers, stack pointers, and record of spin lock ownership.
The first such screen presents information about the processor that caused the
crash; others follow according to the numerical order of their CPU IDs.

EXAMPLES

$ ANALYZE/SYSTEM
VAX/VMS System analyzer

SDA> SHOW CRASH
System crash information
Time of system crash: 25-FEB-1988 11:18:06.84
Version of system: VAX/VMS VERSION 5.0
System Version Major ID/Minor ID: 10/11
VAXcluster node: BIGTOP, a VAX 8800 - primary CPU (left) was booted
Primary CPU ID:

Bitmask of CPUs active/available:
SDA> SHOW PROCESS
%SDA-E-BADPROC, no such process

00000003/00000003

When issued from within the analysis of a running system, the SHOW
CRASH command displays the time the ANALYZE/SYSTEM command was
issued as the "Time of system crash." The display indicates that the VAX
system in use is a VAX 8800 multiprocessing system, the left CPU of which
is the primary CPU. The bit mask indicates that there are two processors
available and both are running.
Note that there is no defined SDA current process at this time.

SDA-94

SYSTEM DUMP ANALYZER
SHOW CRASH
~

ANALYZE/CRASH SYS$SYSTEM

VAX/VMS System dump analyzer
Dump taken on 23-FEB-1988 12:44:30.23
INVEXCEPTN, Exception while above ASTDEL or on interrupt stack
SDA> SHOW CRASH
System crash information_,
Time of system crash: 23-FEB-1988 12:44:30.23
Version of system: VAX/VMS VERSION 5.0
System Version Major ID/Minor ID: 10/11
VAXcluster node: MOOSE, a VAX 8800 - primary CPU (left) was booted
Crash CPU ID/Primary CPU ID:

00/01

Bitmask of CPUs active/available:

00000003/00000003

CPU bugcheck codes:f)
CPU 00 -- INVEXCEPTN, Exception while above ASTDEL or on interrupt stack
1 other -- CPUEXIT, Shutdown requested by another CPU
CPU 00 Processor crash information

CPU 00 reason for Bugcheck: INVEXCEPTN, Exception while above ASTDEL or on interrupt stack@)
Process currently executing on this CPU: NETACP@)
Current image file: $254$DUA200: [SYS6.SYSCOMMON.] [SYSEXE]NETACP.EXE;3
Current IPL: 8

(decimal)~

General registers:
RO = 00000008
R4 = 00000002
R8 = 00000000
AP = OOOOBE34
PSL = 00080009

R1
R5
R9
FP

00080000
8047FC40
00000062
= 7FFE7DDO

R2 = 8047FC40
R6 = 00000036
R10 = 7FFE7D70
SP = 7FFE7D30

R3 = 000003AC
R7 = 00000000
R11 = 0000747C
PC = 80146682

Processor registers:
POBR
POLR
P1BR
P1LR
!CR
TOOR
COR

ISP
KSP
ESP
SSP
USP

= 816EB600

= ooooococ

= 80FFCEOO
= 001FFC5F

SBR
SLR
PCBB
SCBB

01A6A800
00065600
008AF2AO
01A62600

ASTLVL = 00000004
SISR
= 00000000
recs
00000041
SID
067F014F

= FFFFEDEA
REVR1
11121111
NMIFSR = OOOCOOOO
= 2B914COF
REVR2
FFOOFF12
NMIEAR = 2243F830
= 00000001
CPUINFO= 000009F7
MEMCSRO= 000700FO
NBIAO CSRO = 00203810
NBIA1 CSRO = 00000000
8016ACOO
7FFE7D30
7FFE9EOO
= 7FFEDEOO
= 7FF8E590

SDA-95

SYSTEM DUMP ANALYZER
SHOW CRASH

NMI bus silo:
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
Spinlocks currently owned by CPU 00
IOLOCK8
Owner CPU ID
Ownership Depth
CPUs Waiting

Address
IPL
Rank
Index

00
0001
0000

80185E50
08
14
34

CPU 01 Processor crash information
CPU 01 reason for Bugcheck: CPUEXIT, Shutdown requested by another CPU
Process currently executing on this CPU:
Current IPL: 31

None

(decimal)

General registers:
RO = 00000020
R4 = 80487000
R8 = 7FF28E68
AP = 7FF28D90
PSL = 041FOOOO

R1
R5
R9
FP

= 00000000
= 83ED5EOO
= 7FFA2808
= 7FF28D98

R2 = 8000CA78
R6 = 7FFA4188
R10 = 7FFA4000
SP = 80DAFBF8

R3 = 80DAFOOO
R7 = 7FF28EB8
R11 = 7FFE0070
PC = 80765465

Processor registers:
POBR
POLR
P1BR
P1LR
ICR
TODR
COR
ISP
KSP
ESP
SSP
USP

SDA-96

= 83EE8EOO
= 000001C1
= 837FA600
= 001FF935

SBR
SLR
PCBB
SCBB

= 01A6A800
= 00065600
= OOBB62AO
= 01A62600

ASTLVL = 00000004
SISR
= 00000000
recs = 00000041
= 06FF014F
SID

= FFFFE7C1
REVR1 = 11121111
NMIFSR = OOOCOOOO
= 2B914COF
REVR2 = FFOOFF12
NMIEAR = 24080000
= 00000001
CPUINFO= 000009F7
MEMCSRO= 000700FO
NBIAO CSRO = 00203810
NBIA1 CSRO = 00000000
= 80DAFBF8
= 7FFE7EOO
= 7FFE9EOO
= 7FFED04E
= 7FF28D90

SYSTEM DUMP ANALYZER
SHOW CRASH

NMI bus silo:
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

No spinlocks currently owned by CPU 01

This long display reflects the output of the SHOW CRASH command within
the analysis of a system failure that occurred on a VAX 8800 multiprocessing
system.
The first part of the display includes the following information:

Identification of the system and the version of VMS it was running at the
time of the crash

Indication that the failed processor (CPU 00) was not the primary (CPU
01), but requested CPU 01 to take a CPUEXIT bugcheck. (CPU 01 was,
in fact, idle at the time of the crash.)

The next part of the display shows information particular to CPU 00:

CPU 00 encountered an INVEXCEPTN bugcheck while executing the
NETACP process.

Although the next step in the analysis may be to examine the interrupt
stack of CPU 00, the fact that the failure occurred at IPL 8 may be
grounds to suspect that an I/O driver is involved.

At the end of the example, SDA CPU context remains that of CPU 00; its
current process context is that of the NETACP process.

SDA-97

SYSTEM DUMP ANALYZER
SHOW DEVICE

SHOW DEVICE
Displays a list of all devices in the system and their associated data
structures, or displays the data structures associated with a given device
or devices.

FORMAT

PARAMETER

SHOW DEVICE

device-name
}
{ / ADDRESS=ucb-address

device-name
Device or devices for which data structures are to be displayed. There are
several uses of the device-name parameter:
To display the structures
for ...

Action

All devices in the system

Do not specify a device-name (for example,
SHOW DEVICE).

A single device

Specify an entire device-name (for example,
SHOW DEVICE VT A20).

All devices of a certain type
on a single controller

Specify only the device type and controller
designation (for example, SHOW DEVICE RTA
or SHOW DEVICE RTB).

All devices of a certain type
on any controller

Specify only the device type (for example, SHOW
DEVICE RT).

All devices whose names
begin with a certain
character or character
string

Specify the character or character string (for
example, SHOW DEVICE D).

All devices on a single node
or HSC

Specify only the node name or HSC name (for
example, SHOW DEVICE GREEN$).

In a VAXcluster environment, device information is displayed for each device
in the VAXcluster with the specified device-name. You can limit the display
to those devices that are on a particular node or HSC by specifying the node
name or HSC name as part of the device-name (for example, GREEN$D or
GREEN$DB).

QUALIFIER

I ADDRESS=ucb-address
Indicates the device for which data structure information is to be displayed
by the address of its unit control block (UCB). The /ADDRESS qualifier is
thus an alternate method of supplying a device name to the SHOW DEVICE
command. If both the device-name parameter and the /ADDRESS qualifier
appear in a single SHOW DEVICE command, SDA responds only to the
parameter or qualifier that appears first.

SDA-98

SYSTEM DUMP ANALYZER
SHOW DEVICE

DESCRIPTION

The SHOW DEVICE command produces several displays taken from system
data structures that describe the devices in the system configuration.
If you use the SHOW DEVICE command to display information for more
than one device or one or more controllers, it initially produces the DDB
list display to provide a brief summary of the devices for which it renders
information in subsequent screens.

Information in the DDB list appears in six columns, the contents of which
are as follows:
1

Address of the device data block (DDB)

Controller name

Name of the ancillary control process (ACP) or extended QIO processor
(XQP) associated with the device

Name of the device driver

Address of the driver prologue table (DPT)

Size of the DPT

The SHOW DEVICE command then produces a display of information
pertinent to the device controller. This display includes information gathered
from the following structures:
•

Device data block (DDB)

•

Primary channel request block (CRB)

•

Interrupt dispatch block (IDB)

•

Driver dispatch table (DDT)

If the controller is an HSC controller, SHOW DEVICE also displays
information from its system block (SB) and each path block (PB).

Many of these structures contain pointers to other structures and driver
routines. Most notably, the DDT display points to various routines located
within driver code, such as the start I/O routine, unit initialization routine,
and cancel I/O routine.
For each device unit subject to the SHOW DEVICE command, SDA displays
information taken from its unit control block, including a list of all I/O
request packets (IRPs) in its I/O request queue. For certain mass-storage
devices, SHOW DEVICE also displays information from the primary class
driver data block (CDDB), the volume control block (VCB), and the ACP
queue block (AQB). For units that are part of a shadow set, SDA displays a
summary of shadow set membership.
For a detailed explanation of I/O data structures displayed by SDA, consult
the VMS Device Support Manual.

SDA-99

SYSTEM DUMP ANALYZER
SHOW DEVICE

EXAMPLES
iJ

SDA> SHOW DEVICE VTA20
VTA20 ==> LTA20

VT200_Series

UCB address:

8042E4CO

Device status:
00010110 online,bsy,deleteucb
Characteristics: OC040007 rec,ccl,trm,avl,idv,odv
00000200 nnm
Owner UIC [000001,000004]
PID
00010064
Class/Type
42/6E
Def. buf. size
80
DEVDEPEND
180093AO
DEVDEPND2
7962100C
FLCK/DLCK
00000012

Operation count
Error count
Reference count
BOFF
Byte count
SVAPTE
DEVSTS

5793
0
2
0155
0100
804801CO
0000

ORB address
8042E590
DDB address
80CEF2EO
DDT address
807696FB
CRB address
80BC8BOO
IRP address
80BE2BOO
I/0 wait queue
empty

I/O request queue
STATE
C

IRP

PID

80BE2BOO 00010064
nop bufio,func

MODE CHAN

FUNC

WCB

EFN

AST

IOSB

STATUS

COOO

00000000

80127458

7FFA800C

0003

FFCO

This example reproduces the SHOW DEVICE display for a single device unit,
VTA20. Whereas this display lists information from the UCB for VTA20,
including some addresses of key data structures and a list of pending I/O
requests for the unit, it does not display information about the controller
or its device driver. To display the latter sort of information, specify the
device-name as VTA (for example, SHOW DEVICE VTA).

SDA> SHOW DEVICE DU
I/0 data structures

------------------DDB list
-------Address

-------

80DOB3CO
8000B2B8
80DOB9CO
80D08BAO
80D08AEO

Controller

ACP

Driver

DPT

DPT size
--------

F11XQP
F11XQP
F11XQP
F11XQP
F11XQP

DSDRIVER
DSDRIVER
DSDRIVER
DSDRIVER
DSDRIVER

807735BO
807735BO
807735BO
807735BO
807735BO

679D
679D
679D
679D
679D

---------BLUES$DUA
RED$DUA
RED$DUS
BIGTOP$DUA
TIMEIN$DUA

Press RETURN for more.

This excerpt from the output of the SHOW DEVICE DU command illustrates
the format of the DDB list display. In this case, the DDB list concerns itself
with those devices whose device type begins with DU (that is, DUA and
DUS). It displays devices of these types attached to various HSCs (RED$ and
BLUES$) and systems in a VAXcluster (BIGTOP$ and TIMEIN$).
Following the DDB list, SHOW DEVICE DU produces displays for each
controller and each unit on each controller, as illustrated in the next example.

SDA-100

SYSTEM DUMP ANALYZER
SHOW DEVICE

SDA> SHOW DEVICE DUS
I/0 data structures
DDB list
Address

Controller

ACP

Driver

DPT

DPT size

80DOB9CO

RED$DUS

FUXQP

DSDRIVER

807735BO

679D

Controller: RED$DUS
LOVE 8ystem Block (SB) 80DOC500
System ID
OOOOOOOOFFF2
Max message size
66
Max datagram size
62
Local hardware type
HS50
Local hardware vers. 2722722221A3
000000272272

Local software type
Local software vers.
Local software incarn.
SCS poller timeout
SCS poller enable mask

HSC
Y35Q
6DF9E6EO
008FCC83
0002
01

Path Block (PB) 80DOBEAO --Status:

0028

Remote sta. addr.
OOOOOOOOOOOB
Remote state
OOOOOOOOOOOB
Remote hardware rev.
00000225
Remote func. mask
4F710200
Resetting port
05
Handshake retry cnt.
1
Msg. buf. wait queue
empty

Remote port type
Number of data paths
Cables state
Local state
Port dev. name
SCS MSGBUF address
PDT address

HSC
2
A-OK B-OK
OPEN
PAAO
80BCD510
803B38DO

Device Data Block (DDB) 80DOB9CO --Driver name
ACP ident
ACP class

DUD RIVER
F11

PACK

Alloc. class
SB address
UCB address

254
80DOC500
803B9C60

DDT address

80773640

Aux. struct.
Timeout link
Ctrl. init.

803B4150
8039E03C
80773774

FDT size
FDT address
Mnt verify
Cloned UCB

244
80773680
80775BC2
return

Primary Channel Request Block (CRB) 80BF7000
Reference count
17
Due time
00012DCC
IDB address
80DOC440
ADP address
80BF7F70

Wait queue
Timeout rout.

empty
807743D1

Driver Dispatch Table (DDT) 80773640
Errlog buf sz
Start I/O
Alt start I/O
Cancel I/O
RED$DUS3

0
80773B21
return
807763A7

Diag buf sz
Register dump
Unit init
Unsol int
RA81

104
return
80775970
80774602

UCB address:

803B9C60

Device status:
00021810 online,valid,unload,lcl_valid
Characteristics: 1C4D4008 dir,fod,shr,avl,mnt,elg,idv,odv,rnd
000002A1 clu,mscp,srv,nnm

SDA-101

SYSTEM DUMP ANALYZER
SHOW DEVICE

Owner UIC [100001,000063]
PIO
00000000
Alloc . lock ID
00010161
Alloc. class
254
Class/Type
01/15
Def. buf. size
512
DEVDEPEND
04EOOE33
DEVDEPND2
00000000
FLCK/DLCK
00000012

Operation count
Error count
Reference count
Online count
BOFF
Byte count
SVAPTE
DEVSTS
RWAITCNT

55595
0
3
2
0000
OAOO
835C7738
0004
0000

ORB address
803B9D90
DOB address
80DOB9CO
DDT address
80773640
VCB address
80440940
CRB address
80BF7000
PDT address
803B38DO
CDDB address
803B4150
I/0 wait queue
empty

Primary Class Driver Data Block (CDDB) 803B4150 --1040 alcls_set,bshadow
8006 cf_shadw,cf_mlths,cf_this,cf_misc,cf_attn,cf_replc

Status:
Controller Flags:

Allocation class
254
System ID
OOOOFFF2
0000
Contrl. ID
OOOOFFF2
01010000
Response ID
00000000
MSCP Cmd status FFFFFFFF

CORP Queue
Restart Queue
OAP Count
Contr. timeout
Reinit Count
Wait UCB Count

80BD1170
empty
1
75
0
0

DOB address
CRB address
CDDB link
PDT address
Original UCB
UCB chain

8000B2B8
80BF7000
803C01CO
803B38DO
00000000
803B89AO

AQB address
RVT address
FCB queue
Cache blk.
Shadow mem. FL
Shadow mem. BL

80DOBAEO
803B9C60
80BD87BO
8044DA30
80CF5C40
80CF5BEO

*** I/0 request queue is empty ***
--- Volume Control Block (VCB) 80440940
Volume: VMSCMSMASTER
Lock name: VMSCMSMASTER
Status: AO extfid,system
Status2: 15 writethru,mountver,nohighwater
Shadow status: 21 shadmast,mvbegun
Mount count
Transactions
Free blocks
Window size
Vol. lock ID
Block. lock ID
Shadow lock ID

1
3
205989
7
00010167
01A50139
00010168

Rel. volume
Max. files
Rsvd. files
Cluster size
Def. extend sz.
Record size

0
111384
9
3
5
0

Shadow set $254$DUS3 member summary --Volume: JAZZLORE
Physical unit

Primary path

$254$DUA129
$254$DUA139

RED
RED

Member status

Secondary path
-- none --- none --

Shadow set member
Shadow set member

--- ACP Queue Block (AQB) SODOBAEO
ACP requests are serviced by the extended Qio Processor (XQP)
Status: 14 defsys,xqioproc
Mount count

ACP type
ACP class

f11v2

Request queue

00000000

UCB address:

803B9DFO

*** ACP request queue is empty ***
RED$DUS5

SDA-102

RASO

SYSTEM DUMP ANALYZER
SHOW DEVICE

Device status:
00021810 online,valid,unload,lcl_valid
Characteristics: 1C4D4008 dir,fod,shr,avl,mnt,elg,idv,odv,rnd
000002A1 clu,mscp,srv,nnm

The previous example illustrates the output of the command SHOW DEVICE
DUS command, where two shadow sets (RED$DUS3 and RED$DUS5) are
associated with the HSC RED$. There is a controller display for RED$DUS,
and a unit display for each of the two shadow sets.

SDA-103

SYSTEM DUMP ANALYZER
SHOW EXECUTIVE

SHOW EXECUTIVE
Displays the location and size of each loadable image that makes up the
VMS executive.

FORMAT

SHOW EXECUTIVE

PARAMETERS

None.

QUALIFIERS

None.

DESCRIPTION

The VMS executive consists of a fixed portion and a loadable portion. The
fixed portion is known as SYS$SYSTEM:SYS.EXE and consists of three parts:
•

System service dispatch vectors

•

Universal executive routine vectors

•

Globally referenced data cells

The loadable portion consists of a number of independent images that
perform the work of the VMS operating system.
The SHOW EXECUTIVE command lists the location and size of each image
within the loadable portion of the executive image. It can thus enable you to
determine whether a given memory address falls within the range occupied
by a particular loadable image. (Table SDA-5 describes the contents of each
loadable image.)
By default, SDA displays each location within the loadable portion of the
executive as an offset from the beginning of one of the loadable images: for
instance, EXCEPTION+00282. Similarly, those symbols that represent system
services point to the vector region and not the system service's loadable code.
When tracing the course of a system failure through the listings of modules
contained within a given loadable executive image, you may find it useful to
load into the SDA symbol table all global symbols and global entry points
defined within one or all modules that make up the loadable portion of the
executive image. See the description of the READ command for additional
information.
The SHOW EXECUTIVE command usually shows all components of
the executive image, as illustrated in the following example. In rare
circumstances, you may obtain a partial listing. For instance, once it has
loaded the EXCEPTION module (in the INIT phase of system initialization),
the system can successfully post a bugcheck exception and save a crash dump.
Later, if the system should fail sometime during initialization, it may not have
been able to load some of the modules that appear above EXCEPTION in the
SHOW EXECUTIVE display (see the following example).

SDA-104

SYSTEM DUMP ANALYZER
SHOW EXECUTIVE

EXAMPLE
SDA> SHOW EXECUTIVE
VMS Executive Layout

-------------------Image

Base

End

SYSMSG
RECOVERY_UNIT_SERVICES
RMS
CPULOA
LMF$GROUP_TABLE
SYSLICENSE
SYSGETSYI
SYSDEVICE
MESSAGE_ROUTINES
EXCEPTION
LOGICAL_NAMES
SECURITY
LOCKING
PAGE_MANAGEMENT
WORKING_SET_MANAGEMENT
IMAGE_MANAGEMENT
EVENT_FLAGS_AND_ASTS
IO_ROUTINES
PROCESS_MANAGEMENT
ERRORLOG
PRIMITIVE_ IO
SYSTEM_SYNCHRONIZATION
SYSTEM_PRIMITIVES

8015AAOO
80211400
80183600
80182800
80183800
80184000
801B5AOO
80187400
80189000
801CBAOO
801D4600
801D6600
801D8200
801DAEOO
801E2EOO
801E7COO
801EAAOO
801EC400
801F3200
80204COO
80205COO
80207000
80209200

80183600
80212000
801A7EOO
80183200
801B3COO
80185400
80187000
801B8AOO
80lBB600
801D3EOO
801D6000
801D7COO
801DA800
801E2600
801E7200
801EA400
801EBEOO
801F2COO
801F9400
80205600
80206COO
80208COO
8020C400

Length
00028COO

ooooocoo
00024800
OOOOOAOO
00000400
00001400
00001600
00001600
00002600
00008400
00001AOO
00001600
00002600
00007800
00004400
00002800
00001400
00006800
00006200
OOOOOAOO
00001000
00001COO
00003200

The SHOW EXECUTIVE command displays the location and length of the
loadable images included in the VMS executive.

SDA-105

SYSTEM DUMP ANALYZER
SHOW HEADER

SHOW HEADER
Displays the header of the dump file.

FORMAT

SHOW HEADER

PARAMETERS

None.

QUALIFIERS

None.

DESCRIPTION

The SHOW HEADER command produces a 10-column display, each line
of which displays both the hexadecimal and ASCII representation of the
contents of the dump file header in 32-byte intervals. Thus, the first eight
columns, when read right to left, represent the hexadecimal contents of 32
bytes of the header; similarly, the ninth column, when read left to right,
records the ASCII equivalent of the contents. (Note that the period character
(.) in this column indicates an ASCII character that cannot be displayed.)
After it displays the contents of the first header block, the SHOW HEADER
command displays the hexadecimal contents of the saved error log buffers.
See the VAX/VMS Internals and Data Structures manual for a discussion of the
information contained in the dump file header.

EXAMPLE
SDA> SHOW HEADER
Dump file header
7FF03944 7FFED04E
00000000 00000000
00000000 00000000
00020000 00000000
414E454C 45480800
FE9E007F F74D7COA

OOOOOOC1 00000000
00040000 80185200
00000000 00000000
15000011 00000000
0000012C 00000000
00000000 00002020

........................ N... 09 .. 00000000
.R .............................. 00000020
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00000040
................................ 00000060
.... , ..................... GARNER 00000080
........... %.©.o41 ...... M....... OOOOOOAO

80108739 00000300
414E454C 45480800
01080100 OOOOC30A

.... 9 ....... 5 ................... 80108600
.. GARNER ........... &.zxcv.0 ... 80108620
.A ........ d ............ GARNER . 80108640

Saved error log messages
00000000 00000009
7B0090AC 2FCBCEC2
00202041 4E454C45

SDA-106

SYSTEM DUMP ANALYZER
SHOW HEADER

The SHOW HEADER command displays the contents of the dump file's
header from address 6B0 16 to address C90 16 . Ellipses indicate hexadecimal
information omitted from the display.

SDA-107

SYSTEM DUMP ANALYZER
SHOW LOCK

SHOW LOCK
Displays information about all lock management locks in the system, or
about a specified lock.

FORMAT

PARAMETERS

SHOW LOCK

lock-id }
{ /ALL

lock-id
Name of a specific lock.

QUALIFIER

/ALL
Lists all locks that exist in the system. This is the default behavior of the
SHOW LOCK command.

DESCRIPTION

The SHOW LOCK command displays the information described in
Table SDA-7 for each lock management lock in the system, or for the
lock indicated by lock-id. (Use the SHOW SPINLOCK command to display
information about spin locks.) You can obtain a similar display for the locks
owned by a specific process by issuing the appropriate SHOW
PROCESS /LOCKS command. See the VMS System Services Reference Manual
for additional discussion of the significance of this information.
You can display information about the resource to which a lock is queued by
issuing the SHOW RESOURCE command specifying the resource's lock-id.
Table SDA-7

Contents of the SHOW LOCK and SHOW PROCESS
/LOCKS Displays

Display Element

Description

Process Index 1

Index into the PCB array to a pointer to the process
control block (PCB) of the process that owns the lock

Name 1

Name of the process that owns the lock

Extended PIO

Clusterwide identification of the process that owns the
lock

Lock ID

Identification of the lock

PIO

Systemwide identification of the lock

Flags

Information specified in the request for the lock

Par. ID

Identification of the lock's parent lock

Granted at

Lock mode at which the lock was granted

Su blocks

Identification numbers of the locks that the lock owns

1 This display element is produced only by the SHOW PROCESS/LOCKS command.

SDA-108

SYSTEM DUMP ANALYZER
SHOW LOCK

Table SDA-7 (Cont.)

Contents of the SHOW LOCK and SHOW
PROCESS/LOCKS Displays

Display Element

Description

LKB

Address of the lock block (LKB). If a blocking AST
has been enabled for this lock, the notation "BLKAST'
appears next to the LKB address.

Resource

Dump of the resource name. The two leftmost columns
of the dump show its contents as hexadecimal values, the
least significant byte being represented by the rightmost
two digits. The rightmost column represents its contents
as ASCII text, the least significant byte being represented
by the leftmost character.

Status

Status of the lock, information used internally by the VMS
lock manager.

Length

Length of the resource name.
Processor access mode of the name space in which the
resource block (RSB) associated with the lock resides.
Owner of the resource. Certain resources owned by
the VMS operating system list "System" as the owner.
Resources owned by a group have the number (in octal)
of the owning group in this field.
Indication of whether the lock is mastered on the local
system or is a process copy.

EXAMPLE
SDA> SHOW LOCK
Lock database
Lock id: 00010001
PID:
00000000
NOQUEUE SYNCSTS SYSTEM
Flags:
CVTSYS
Par. id: 00000000
Granted at
EX
Sublocks:
1
LKB:
80DOB8AO
SYS$SYS_ Status: NOQUOTA
Resource:
5F535953 24535953
00000000 4C774449
IDwL ....
Length
16
Exec. mode
00000000 00000000
00000000 00000000
System
Local copy
Lock id: 00010004
CONVERT SYNCSTS CVTSYS
PID:
00000000
Flags:
Par. id: 00000000
Granted at
CR
Sublocks:
16
LKB:
80D091AO
BLKAST
F11B$vVM Status: NOQUOTA
Resource:
40567624 42313146
20204E41 4A353153
S15JAN
Length
18
Kernel mode
00000000 00002020
00000000 00000000
System
Local copy

SDA-109

SYSTEM DUMP ANALYZER
SHOW LOCK

Lock id: 00280009
PID:
00000000
Flags:
VALBLK CONVERT SYNCSTS
Par. id: 00000000
Granted at
CR
NOQUOTA CVTSYS
Sublocks:
0
LKB:
80CDA880
SYS$_KAR Status: MSTCPY
Resource:
52414B5F 24535953
Length
17
30415544 24455441
ATE$DUAO
Kernel mode
00000000 0000003A
System
00000000 00000000
Master copy of lock 001COOF5 on system 000100A1

SDA> SHOW RESOURCE/LOCK=280009
Resource database
Address of RSB: 80BD2150 Group grant mode:
CR
Parent RSB:
00000000 Conversion grant mode: CR
Sub-RSB count:
0 BLKAST count:
0
Value block:
00000000 00000000 00000000 00000019
Seq. #: 0000002D
SYS$_KAR
Resource:
52414B5F 24535953
Length
17
30415544 24455441
ATE$DUAO
CSID: 00000000
Kernel mode
00000000 0000003A
........
........
System
00000000 00000000
Granted queue (Lock ID I Gr mode):
OODA1269 CR
00280009 CR
00270B9F CR
OOD70BFE CR
OOOD1017 CR
00601418 CR
OOOF1964 CR
000200DF CR

0094054D
OOODOF4F
01131450

CR
CR
CR

Conversion queue (Lock ID I Gr/Rq mode):
*** EMPTY QUEUE ***
Waiting queue (Lock ID I Rq mode):
*** EMPTY QUEUE ***

This SDA session shows the output of the SHOW LOCK command for
several locks. The SHOW RESOURCE command, executed for the last
displayed lock, verifies that the lock is in the resource's granted queue,
among many other locks given concurrent read (CR) access to the resource.
(See Table SDA-13 for a full explanation of the contents of the display of the
SHOW RESOURCE command.)

SDA-110

SYSTEM DUMP ANALYZER
SHOW PAGE_TABLE

SHOW PAGE_TABLE
Displays a range of system page table entries, the entire system page
table, or the entire global page table.

FORMAT
PARAMETER

QUALIFIERS

SHOW PAGE_TABLE

[/qualifier{, ... ]] [range}

range
Range of virtual addresses for which SDA is to display page table entries.
You can express a range using the following syntax:
m:n

Range of virtual addresses from m to n

m;n

Range of virtual addresses starting at m and continuing for n bytes

/GLOBAL
Lists the global page table.

/SYSTEM
Lists the system page table.

/ALL
Lists both the global and system page tables. This is default behavior of
SHOW PAGE_TABLE.

DESCRIPTION

For each virtual address displayed by the SHOW PAGE_TABLE command,
the first six columns of the listing provide the associated page table entry and
describe its location, characteristics, and contents (see Table SDA-8). SDA
obtains this information from the system page table.
If the virtual page has been mapped to a physical page, the last nine columns
of the listing include information from the page frame number (PFN) database
(see Table SDA-9). Otherwise, the section is left blank.

SDA indicates pages are inaccessible by displaying the following message:
-------- n NULL PAGES

Here, n indicates the number of inaccessible pages.

SDA-111

SYSTEM DUMP ANALYZER
SHOW PAGE_TABLE

Table SDA-8
Value

Meaning

ADDRESS

System virtual address that marks the base of the virtual page

SV APTE

System virtual address of the page table entry that maps the virtual
page

PTE

Contents of the page table entry, a longword that describes a system
virtual page

Type

Type of virtual page. There are the following eight types:

Type

Meaning

VALID

Valid page (in main memory)

TRANS

Transitional page (between main memory and page lists)

DZERO

Demand-allocated, zero-filled page

PGFIL

Page within a paging file

STX

Section table's index page

GPTX

Index page for a global page table

IOPAG

Page in 1/0 address space

NXMEM

Page not represented in physical memory. The page
frame number (PFN) of this page is not mapped by any
of the system's memory controllers. This indicates an
error condition.

PROT

Protection: a code, derived from bits in the PTE, that designates
the type of access (read and/or write) granted to processor access
modes (kernel, executive, supervisor, or user)

Bits

Letters that represent the setting of a bit or a combination of bits
in the PTE. These bits indicate attributes of a page. The following
codes are listed:

Code

SDA-112

Virtual Page Information in the SHOW PAGE_TABLE
Display

Meaning

Page has been modified.

Page is locked into a working set.

Owner can access the page in kernel mode.

Owner can access the page in executive mode.

Owner can access the page in supervisor mode.

Owner can access the page in user mode.

SYSTEM DUMP ANALYZER
SHOW PAGE_TABLE

Table SDA-9

Physical Page Information in the SHOW PAGE_
TABLE Display

Category

Meaning

PAGTYP

Type of physical page, one of the following six types:

LOC

Page Type

Meaning

PROCESS

Page is part of process space.

SYSTEM

Page is part of system space.

GLOBAL

Page is part of a global section.

PPGTBL

Page is part of a process's page table.

GPGTBL

Page is part of a global page table.

GBLWRT

Page is part of a global, writable section.

Location of the page within the system, one of the following eight
types:

Location

Meaning

ACTIVE

Page is in a working set.

MDFYLST

Page is in the modified page list.

FREELST

Page is in the free page list.

BADLST

Page is in the bad page list.

RELPEND

Release of the page is pending.

RDERROR

Page has had an error during an attempted read
operation.

PAGEOUT

Page is being written into a paging file.

PAGEIN

Page is being brought into memory from a paging file.

STATE

Byte that describes the state of the physical page.

TYPE

Byte that describes the type of virtual page. The types in this
column are the hexadecimal codes that stand for the page types
that appear in column PAGTYP of this display, described previously.

REFCOUNT

Count of the pro.cesses that are referencing this PFN. If the value of
REFCOUNT is nonzero, the page is used in at least one working set.
If the value is zero, the page is not used in any working set.

BAK

Address of the backing store; location on a disk device to which
pages can be written.

SVAPTE

Virtual address associated with this page frame. The two SV APTEs
indicate a valid link between physical and virtual address space.

FLINK

Forward link within PFN database that points to the next virtual
page; this longword also acts as the count of the number of
processes that are sharing this global section.

BLINK

Backward link within PFN database; also acts as an index into the
working set list.

SDA-113

SYSTEM DUMP ANALYZER
SHOW PAGE_TABLE

EXAMPLE
SDA> SHOW PAGE_TABLE

System page table

----------------ADDRESS

SVAPTE

PTE TYPE

PROT

8AD22EOO F8020725
8AD22E04 f 8020726
8AD22E08 F8020727
8AD22EOC F8020728
8AD22E10 F8020729
8AD22E14 EC02072A
8AD22E18 F402072B

VALID UR
VALID UR
VALID UR
VALID UR
VALID UR
VALID UREW
VALID URKW

8AD22FEC F801F10E
8AD22FFO F801F10F
8AD22FF4 F801F173
8AD22FF8 F801F172
8AD22FFC F801F17F
8AD23000 F801F17E
8AD23004 7801EBC6

VALID UR
VALID UR
VALID UR
VALID UR
VALID UR
VALID UR
TRANS UR

SDA-114

BITS PAGTYP

LDC STATE TYPE REFCNT BAK

SVAPTE

FLINK

8AD22FEC
8AD22FFO
8AD22FF4
8AD22FF8
8AD22FFC
8AD23000
8AD23004

00000000 00000258
00000000 00000257
00000000 000004B1
00000000 00000301
00000000 OOOOOOF5
00000000 00000174
OOOOD38B 0001EBC7

BLINK

K
K
K
K
K
M K
M K

K SYSTEM ACTIVE 07
K SYSTEM ACTIVE 07
K SYSTEM ACTIVE 07
K SYSTEM ACTIVE 07
K SYSTEM ACTIVE 07
K SYSTEM ACTIVE 07
K SYSTEM FREELST 00

01
01
01
01
01
01
01

1 0040FFF8
1 0040FFF8
1 0040FFF8
1 0040FFF8
1 0040FFF8
1 0040FFF8
0 0040FFF8

SYSTEM DUMP ANALYZER
SHOW PFN_DATA

SHOW PFN_DATA
Displays information that is contained in the page lists and PFN database.

FORMAT
PARAMETER

SHOW PFN_DATA {pfn] {/qualifier}
pfn
Page frame number (PFN) of the physical page for which information is to be
displayed.

QUALIFIERS

/ALL
Displays the free page list, modified page list, and bad page list. This is the
default behavior of the SHOW PFN _DATA command. SDA precedes each
list with a count of the pages it contains and its low and high limits.

/BAD
Displays the bad page list. SDA precedes the list with a count of the pages it
contains, its low limit, and high limit.

/FREE
Displays the free page list. SDA precedes the list with a count of the pages it
contains, its low limit, and high limit.

/MODIFIED
Displays the modified page list. SDA precedes the list with a count of the
pages it contains, its low limit, and high limit.

/SYSTEM
Displays the entire PFN database in order by page frame number, starting at
PFN 0000.

DESCRIPTION

For each page frame number it displays, the SHOW PFN _DATA command
lists information used in translating physical page addresses to virtual page
addresses. Table SDA-10 lists the contents of the display.

SDA-115

SYSTEM DUMP ANALYZER
SHOW PFN_DATA

Table SDA-10
Item

Contents

PFN

Page frame number

PTE ADDRESS

System virtual address of the page table entry that describes
the virtual page mapped into this physical page

BAK

Place to find information on this page when all links to this PTE
are broken: either an index into a process section table or the
number of a virtual block in the paging file

REFCNT

Number of references being made to this page

FLINK

Address of the next page in the list in which this virtual page
currently resides

BLINK

Address of the previous page in the list in which this virtual
page currently resides

TYPE

Type of virtual page, one of the following:

ST ATE

SDA-116

Page Frame Number Information in the SHOW
PFN_DATA Display

Code

Meaning

00
01
02
03
04
05

Process page
System page
Global, read-only page
Global, read/write page
Process page-table page
Global page-table page

State of the virtual page, the low nibble of which can be one of
the following:

Code

Meaning

Page is on the free page list.

Page is on the modified page list.

Page is on the bad page list.

Release of the page to the free or modified page list is
pending.

Error occurred as the page was being read from the
disk.

Modified page writer is currently writing the page to
the disk.

Page fault handler is currently reading the page from
the disk.

Page is active and valid.

SYSTEM DUMP ANALYZER
SHOW PFN_DATA

EXAMPLE
SDA> SHOW PFN_DATA
Free page list
Count:
225
Low limit:
57
High limit: 1073741824
PFN

PTE ADDRESS

BAK

----------- -------1329
1963
017C
14B4
1529
1485

8047AF3C
8047AB10
8047B3F8
8047B464
8047AA34
8047AC80

03002A83
03002A43
03002A84
03002A85
03002A87
030010B3

REFCNT FLINK BLINK
----- ----1963 0000
0
0
017C 1329
14B4 1963
0
1529 017C
0
1485 14B4
0
0
1707 1529

TYPE

STATE

---------- ---------00 PROCESS
00 PROCESS
00 PROCESS
00 PROCESS
00 PROCESS
00 PROCESS

00 FREELST
00 FREELST
00 FREELST
00 FREELST
00 FREELST
00 FREELST

The SHOW PFN _DATA command displays the information shown
previously for the free page list, the modified page list, and the bad page
list, and then all of the PFN database, including the first three lists.

SDA-117

SYSTEM DUMP ANALYZER
SHOW POOL

SHOW POOL
Displays information about the disposition of memory, paged and
nonpaged, including the lookaside lists (SRP, IRP, and LRP), nonpaged
dynamic storage pool, and paged dynamic storage pool.

FORMAT
SHOW POOL

/FREE
/HEADER

/SUMMARY
/TYPE=block-type J

PARAMETERS

QUALIFIERS

range
/ALL
//RP
/LRP
/NONPAGED
/PAGED
J
/SRP

range

Range of virtual addresses in pool that SDA is to examine. You can express a
range using the following syntax:
m:n

Range of virtual addresses in pool from m to n

m;n

Range of virtual addresses in pool starting at m and continuing for n bytes

/ALL
Displays the entire contents of allocated pool, including the lookaside lists,
nonpaged dynamic storage pool, and paged dynamic storage pool. This is the
default behavior of the SHOW POOL command.

/FREE
Displays the entire contents, both allocated and free, of the specified region
or regions of pool. You cannot use the /FREE qualifier when you use a range
to indicate a region of pool to be displayed.

/HEADER
Displays only the first 16 longwords of each data block found within the
specified region or regions of pool.

//RP
Displays the contents of the 1/0 request packets (IRPs) currently in use.

/LRP
Displays the contents of the large request packets (LRPs) currently in use.

/NONPAGED
Displays the contents of the nonpaged dynamic storage pool currently in use.

/PAGED
Displays the contents of the paged dynamic storage pool currently in use.

SDA-118

SYSTEM DUMP ANALYZER
SHOW POOL

/SRP
Displays the contents of the small request packets (SRPs) currently in use.

/SUMMARY
Displays only an allocation summary for each specified region of pool.

/TYPE=block-type
Displays the blocks within the specified region or regions of pool that are
of the indicated block-type. If SDA finds no blocks of that type in the pool
region, it displays a blank screen, followed by an allocation summary of the
region.

DESCRIPTION

The SHOW POOL command displays information about the contents of
any specified region of pool in an 8-column format. The contents of the full
display, from left to right, are listed as follows:
Column 1 contains the type of control block that starts at the virtual address
in pool indicated in column 2. If SDA cannot interpret the block type, it
displays a block type of "UNKNOWN." Column 3 lists the number of bytes
(in decimal) of memory allocated to the block. The block size is fixed for
SRPs, IRPs, and LRPs, and is variable in the paged and nonpaged pools.
The remaining columns contain a dump of the contents of the block, in 4longword intervals, until the block is complete. Columns 4 through 7 display,
from right to left, the contents in hexadecimal; column 8 displays, from left
to right, the contents in ASCII. If the ASCII value of a byte is not a printing
character, SDA displays a period character (.) instead.
For each region of pool it examines, the SHOW POOL command displays
an allocation summary. This 4-column table lists, in column 2, the types
of control block identified in the region and records the number of each in
column 1. The last two columns represent the amount of the pool region
occupied by each type of control block: column 3 records the total number
of bytes and column 4 the percentage. The summary concludes with an
indication of the number of bytes used within the particular pool region,
as well as the number of bytes remaining. It provides an estimate of the
percentage of the region that has been allocated.

SDA-119

SYSTEM DUMP ANALYZER
SHOW POOL

EXAMPLES
iJ

SDA> SHOW POOL
IRP lookaside list
Dump of blocks allocated from IRP lookaside list
CIMSG

80BADEOO

208
001000DA 003C0090 OOOOA900 00036FFO .o ........ < ... .
D9B3001C 00000000 AOB5001D 35E60017 ... 5 ........... .
41414141 00000600 65EA0004 00000600 ....... e .... AAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA

FCB

80BAE070

208
00000000 00070000 80BAECAO 80BD9B30 0 .............. .
00000000 00000000 80BAE080 80BAE080 . . . . . . . . . . . . . .. .
00000001 00000002 OOOC017B 00010000 .... { .......... .
00000001 00000003 0000023E 0000606C l' .. > .......... .

IRP

80BAE140

208
00010001 410AOOC4 0015D9AO 0015D9AO ........... A... .
80431820 00000000 7FFA2808 80127458 Xt ........... C.
80422450 1019FF80 7FFA2814 1C1D0032 2 ........... P$B.
61616161 80431820 00000000 000601B9 ......... C.aaaa

The SHOW POOL command lists the used contents of the IRP lookaside list,
among which are the CI message block (CIMSG), file control block (FCB), and
I/O request packet (IRP). When it completes the listing for the IRP lookaside
list, it displays a summary of IRP allocation information.
The SHOW POOL command continues, displaying similar information for the
other regions of pool-the LRP and SRP lookaside lists, nonpaged dynamic
storage pool, and paged dynamic storage pool.
~

SDA> SHOW POOL GOBADE00;260
Non-paged dynamic storage pool
Dump of blocks allocated from non-paged pool
CIMSG

SDA-120

80BADEOO

144
001000DA 003C0090 OOOOA900 00036FFO .o ........ < .... .
D9B3001C 00000000 AOB5001D 35E60017 ... 5 ........... .
41414141 00000600 65EA0004 00000600 ....... e .... AAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA

SYSTEM DUMP ANALYZER
SHOW POOL

UNKNOWN 808ADE90

112
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA

CIDG

808ADEDO

144
80770888 00380090 0004D7EO 000008FO .......... ; ... w.
61616161 61616161 61616161 016CE87C .. l.aaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa

UNKNOWN 808ADF60

64
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa

CIDG

808ADFAO

144
80770888 00380090 0003FFCO 00048180 .......... ; ... w.
61616161 61616161 61616161 016CE94C L.l.aaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa

UNKNOWN 808AE030

48
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa

Summary of non-paged pool contents
3

UNKNOWN
CIDG
1 CIMSG

176
288
144

(29%)
(48%)
(24%)

Total space used = 608 out of 608 total bytes, O bytes left
Total space utilization = 100%

The preceding example examines 608 (260 16 ) bytes of nonpaged pool, starting
at address 80BADE00 16 , which happens to be the starting address of the
CIMSG block listed in the previous example's output. SDA attempts to
identify allocated blocks as it proceeds through the specified region of pool,
and displays an allocation summary when it completes the listing.

SDA-121

SYSTEM DUMP ANALYZER
SHOW POOL

SDA> SHOW POOL/FREE
!RP lookaside list
Dump of blocks allocated from !RP lookaside list
CIMSG

80BADEOO

208
001000DA 003C0090 OOOOA900 00036FFO .o ............. .
D9B3001C 00000000 AOB5001D 35E60017 ... 5 ........... .
41414141 00000600 65EA0004 00000600 ....... e .... AAAA
41414141 41414141 41414141 41414141 AAAAAAAAAAAAAAAA

[Free]

80BADEDO

208
807708BB 003B0090 0004D7EO 000008FO .......... ; ... w.
61616161 61616161 61616161 016CE87C .. l.aaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa

[Free]

80BADFAO

208
807708BB 003B0090 0003FFCO 0004B1BO .......... ; ... w.
61616161 61616161 61616161 016CE94C Ll.aaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa
61616161 61616161 61616161 61616161 aaaaaaaaaaaaaaaa

The SHOW POOL/FREE command produces a display similar in format and
extentto that presented in Example 1. However, it displays the unallocated
portions of pool in addition to those that are used.
~

SDA> SHOW POOL/PAGED/HEADER
Paged dynamic storage pool
Dump of blocks allocated from paged pool
RSHT

8024FEOO

LNM

80250010

LNM

80250070

LNM

802500AO

LNM

80250100

528
802DC710 00380210 00000000 FFFFFF80 .......... 8 ... -.
96
8015B847 00400060 802D75AO 00000000 ..... u-.' .©.G ...
48
8015B847 01400030 802500AO 80207400 .t- ... %.0.©.G ...
96
8015B847 02400060 802DC170 80250070 p.%.p.-.' .©.G ...
48
8015B847 00400030 802DC510 802E1B60 ' ..... -.0.©.G ...

The SHOW POOL/PAGED /HEADER command displays only the name of
each block allocated from paged pool, its starting address, its size, and the
first four longwords of its contents.

SDA-122

SYSTEM DUMP ANALYZER
SHOW PORTS

SHOW PORTS
Displays those portions of the port descriptor table (PDT) that are port
independent.

FORMAT

SHOW PORTS

PARAMETERS

None.

QUALIFIER

/ADDRESS=pdt-address

[/ADDRESS=pdt-address]

Displays the specified port descriptor table (PDT). 11

DESCRIPTION

The SHOW PORTS command provides port-independent information from
the port descriptor table (PDT) for those CI ports with full SCS connections.
This information is used by all system communications services (SCS) port
drivers.
Note that the SHOW PORTS command does not display similar information
about UDA ports, BDA ports, and similar controllers.
The SHOW PORTS command produces several displays. The initial display,
the PDT summary page, lists the PDT address, port type, device name, and
driver name for each PDT. Subsequent displays provide information taken
from each PDT listed on the summary page.
You can use the /ADDRESS qualifier to the SHOW PORTS command to
produce more detailed information about a specific port. The first display
of the SHOW PORTS/ ADDRESS command duplicates the last display of
the SHOW PORTS command, listing information stored in the port's PDT.
Subsequent displays list information about the port blocks and virtual circuits
associated with the port.

You can find the pdt-address for any active connection on the system in the PDT summary page display of
the SHOW PORTS command. In addition, CDT addresses are also stored in many individual data structures
related to SCS connections: for instance in the path block displays of the SHOW CLUSTER/SCS command.

SDA-123

SYSTEM DUMP ANALYZER
SHOW PORTS

EXAMPLES
iJ

SDA> SHOW PORTS
VAXcluster data structures
PDT Summary Page
PDT Address

Type

Device

Driver Name

803B38DO
803CD6DO

pa
pe

PAAO
PEAO

PADRIVER
PED RIVER

Port Descriptor Table (PDT) 803B38DO --Type: 01 pa
Characteristics: 0000
Msg Header Size
32
Max Xf er Bent
FFFFFFFF
DG Header Size
136
Poller Sweep
21
Fork Block W.Q.
empty
UCB Address
803B34FO
ADP Address
80BF7F70
Accept
807725ED
Alloc_Dg_Buf
80773102
Alloc_Msg_Buf
80772F69
Dealloc_Msg_Buf
80773047
Dealloc_Msg_Buf _Reg 8077305A

807725AO Recyclh_Msg_Buf 80772FEE
Connect
Dealloc_Dg_Buf 807731E6 Request_Data
8077338D
80772661 Send_Data
807733D6
Disconnect
8077324A
Unmap
8077344A Send_Dg_Buf
80773108
Map
807732E5 Send_Msg_Buf
Map_Bypass
807732CC Send_Cnt_Msg_Buf 8077310F
Map_Irp
807732D5 Read_ Count
8076FE90
Map_Irp_Bypass 807732C4 Rls_Read_Count
8076FEFE
Queue_Dg_Buf
807722B7
807731EC Mreset
Queue_Mult_Dgs 807731F4 Ms tart
807722C1
80772304
Recycl_Msg_Buf 80772FF8 Stop_Vcs
8077323D
8077262C Send_Dg_Reg
Reject

--- Port Descriptor Table (PDT) 803CD6DO --Type: 03 pe
Characteristics: 0000
Msg Header Size

Connect

803C9DFC

Recyclh_Msg_Buf

803CA84A

The SHOW PORTS command first lists the two SCS ports that exist within
the VAXcluster and then displays information obtained from each port
descriptor table (PDT).

SDA-124

SYSTEM DUMP ANALYZER
SHOW PORTS

SDA> SHOW PORTS/ADDRESS=G3CD6DO
VAXcluster data structures
--- Port Descriptor Table (PDT) 803CD6DO --Type: 03 pe
Characteristics: 0000
32

Msg Header Size

Connect

803C9DFC

Recyclh_Msg_Buf

803CA84A

--- Port Block 80B7CCAO
Status: 0001 authorize
VC Count: 12
Secs Since Last Zeroed: 77188
SCXB Size
SCXB Count
SCXB Max
SCXB Queue Empty
No SCXB for ACK
Bus
0
0

268
26
26
4553
47

LCXB Size
LCXB Count
LCXB Max
LCXB Queue Empty

Error Count

Last Error

Time of Last Error

-----------

----------

-----------------------

0
2

00390334

23-FEB-1988 12:43:14.99

1780
30
30
0

Virtual Circuit (VC) 803C0030 --Remote System Name: BLUES
Local System ID: 223 (DF)
Msg Xmt
Unsequence
Sequence
ReXmt
ACK
Chan Cntl
Bytes Xmt

6 Msg Rev
3
Unsequence
0
Sequence
0
Re Rev
0
ACK
Cache
3
165
Ill Seq
Chan Cntl
Bad Chksum
TR Short
CC Short
CC Bad ECO
Bytes Rev

Remote System ID: AA-00-04-00-77-4C
Status: 0005 open.path
25736
3
0
0
0
0
0
25733
0
0
0

Auth fail
No RcvChan
No XmtChan
Ill ACK
SeqMsg TMO
Listen TMO
CC HS TMO
TR DFQ Empty
TR MFQ Empty
CC DFQ Empty
CC MFQ Empty

0
0
0
0
0
0
0
0
0
0
0

1182733

--- Virtual Circuit (VC) 803DE9AO --Remote System Name: GREENS
Local System ID: 222 (DE)

Remote System ID: AA-00-04-00-79-4C
Status: 0005 open.path

The SHOW PORTS/ ADDRESS command first provides a summary of port
information obtained from the PDT located at 803CD6D0 16 . It then displays
information from the associated port block and a screen describing each of its
12 virtual circuits.

SDA-125

SYSTEM DUMP ANALYZER
SHOW PROCESS

SHOW PROCESS
Displays the software and hardware context of any process in the balance
set.

FORMAT
SHOW PROCESS [/qualifier{, ... }]

[~~~~;;:~~me
/SYSTEM

PARAMETERS

ALL
Shows information about all processes that exist in the system.

process-name
Name of the process for which information is to be displayed. 12
You can determine the names of the processes in the system by issuing a
SHOW SUMMARY command.
The process-name can contain up to 15 letters and numerals, including
the underscore (-) and dollar sign ( $) characters. If it contains any other
characters, you must enclose the process-name in quotation marks (" ").

QUALIFIERS

/ALL
Displays all information shown by the following qualifiers: /PCB, /PHD,
/REGISTERS, /WORKING_SET, /PROCESS_SECTION_TABLE, /PAGE_
TABLES, and /CHANNEL.

/CHANNEL
Displays information about the 1/0 channels assigned to the process.

/INDEX=nn
Specifies the process for which information is to be displayed by its index into
the system's list of software process control blocks (PCBs). You can supply
either of the following values for nn:
•

The process index itself

•

The process identification (PID) or extended PID longword, from which
SDA extracts the correct index

To obtain these values for any given process, issue the SDA command SHOW
SUMMARY.

Use of the process-name parameter, the /INDEX qualifier, or the /SYSTEM qualifier causes the SHOW
PROCESS command to perform an implicit SET PROCESS command, making the indicated process the current
process for subsequent SDA commands. (See the description of the SET PROCESS command and Section 4 for
information on how this can affect the process context-and CPU context-in which SDA commands execute.)

SDA-126

SYSTEM DUMP ANALYZER
SHOW PROCESS

/LOCKS
Displays the lock management locks owned by the current process.
The /LOCKS qualifier produces a display similar in format to that produced
by the SHOW LOCKS command. See Table SDA-7 for additional
information.

/PO
Displays the page tables for PO space. See the description of the /PAGE_
TABLES qualifier.

/P1
Displays the page tables for Pl space. See the description of the /PAGE_
TABLES qualifier.

/PAGE_ TABLES [

/~~ge ]
/P1

Displays the page tables of the process's program (PO) and control (Pl)
regions, or, optionally, either page table or the page table entries for a range
of addresses.
You can express a range using the following syntax:
m:n

Displays the page table entries that correspond to the range of virtual
addresses from m to n

m;n

Displays the page table entries that correspond to a range of n pages,
starting with page m

/PCB
Displays the information contained in the software process control block
(PCB). This is the default behavior of the SHOW PROCESS command.

/PHD
Lists information included in the process header (PHD).

/PROCESS_SECTION_ TABLE
Lists the information contained in the process section table (PST).

/REGISTERS
Lists the hardware context of the process, as reflected in the process's registers
stored in the hardware PCB and-if the process is current on a processor in
the VAX system-the processor's registers.

/RMS[=option[, ... ]]
Displays certain specified RMS data structures for each image 1/0 or process
permanent 1/0 file the process has open. To display RMS data structures for
process-permanent files, specify the PIO option to this qualifier.

SDA-127

SYSTEM DUMP ANALVZER
SHOW PROCESS

SDA determines the structures to be displayed according to either of the
following methods:
•

If you provide the name of a structure or structures in the option
parameter, SHOW PROCESS/RMS displays information from only
the specified structures. (See Table SDA-6 for a list of keywords that
may be supplied as options.)

•

If you do not specify an option, SHOW PROCESS/RMS displays the
current list of options as shown by the SHOW RMS command and set by
the SET RMS command.

/SYSTEM

Displays the system process control block. 13 The system PCB and process
header (PHD) are dummy structures that are located in system space. These
structures contain the system working set, global section table, global page
table, and other systemwide data.

/WORKING_SET
Displays the process's working set list.

DESCRIPTION

The SHOW PROCESS command displays information about the process
specified by process-name, the process specified in the /INDEX qualifier, the
system process, or all processes. The SHOW PROCESS command performs
an implicit SET PROCESS command under certain uses of its qualifiers and
parameters, as noted above. By default, the SHOW PROCESS command
produces information about the SDA current process, as defined in Section 4.
The default of the SHOW PROCESS command provides information taken
from the software process control block (PCB). 14 This information describes
the following characteristics of the process:
•

Software context

•

Condition-handling information

•

Information on interprocess communication

•

Information on counts, quotas, and resource usage

Among the displayed information are the process's PID, EPID, priority, job
information block (JIB) address, and process header (PHD) address. SHOW
PROCESS also describes the resources owned by the process, such as event
flags and mutexes. The "State" field records the process's current scheduling
state; in a VMS multiprocessing system, the display indicates the CPU ID of
any process whose state is CUR.
The SHOW PROCESS/ ALL command displays additional process-specific
information, also provided by several of the individual qualifiers to the
command.

SDA-128

SYSTEM DUMP ANALYZER
SHOW PROCESS

The process header display, also produced by the /PHD qualifier, provides
information taken from the process header (PHD), which is swapped into
memory when the process becomes part of the balance set. Each item listed
in the display reflects a quantity, count, or limit for the process's use of the
following resources:

•
•

The pager

•

The scheduler

•

Asynchronous system traps

•

I/O activity

•

CPU activity

Process memory

The process registers display, also produced by the /REGISTERS qualifier,
describes the process's hardware context, as reflected in its registers.
There are two places where a process's hardware context is stored, as
described below:
•

If the process is currently executing on a processor in the VAX system
(that is, in the CUR scheduling state), its hardware context is contained
in that processor's registers. (That is, the process's registers and the
processor's registers contain identical values, as illustrated by a SHOW
CPU command for that processor or a SHOW CRASH command if the
process was current at the time of the system failure.)

•

If the process is not executing, its hardware context is stored in the part
of the PHD known as the hardware PCB.

The process registers display first lists those registers stored in the hardware
PCB ("Saved process registers"). If the process to be displayed is currently
executing on a processor in the VAX system, the display then lists the
processor's registers ("Active registers for the current process"). In each
section, the display lists the registers in the following groups:
•

General purpose registers (RO through Rll, the AP, FP, and PC)

•

Stack pointers (KSP, ESP, SSP, and USP)

•

Special-purpose registers (PC and PSL)

•

Base and length registers (POBR, PlBR, POLR, and Pl LR)

The working set information and working set list displays, also produced
by the /WORKING_SET qualifier, describe those virtual pages that the
process can access without a page fault. After a brief description of the size,

SDA-129

SYSTEM DUMP ANALYZER
SHOW PROCESS

scope, and characteristics of the working set list itself, SDA displays the
following information for each entry in the working set list:
Column

Contents

INDEX

Index into the working set list at which information for this entry can
be found

ADDRESS

Virtual address of the page in the process address space that this
entry describes

STATUS

Three columns that list the following status information:
•

Page type

•

Location of the page in physical memory

•

Indication of whether the page is locked into the working set

When SDA locates one or more unused working set entries, it issues the
following message:
--- n empty entries

In this message, n is the number (in decimal) of contiguous, unused entries.
The process section table information and process section table displays,
also produced by the /PROCESS_SECTION _TABLE qualifier, list each entry
in the process section table (PST) and display the offsets to the first free entry
and last used entry.
SDA displays the information listed in Table SDA-11 for each PST entry.
Table SDA-11

Process Section Table Entry Information in the
SHOW PROCESS Display

Part

Definition

INDEX

Offset into the PST at which the entry is found. Because entries
in the process section table begin at the highest location in
the table, and the table expands toward lower addresses, the
following expression determines the address of an entry in the table:

PHD + PSTBASOFF-INDEX.

SDA-130

ADDRESS

Virtual address that marks the beginning of the first page of the
section described by this entry.

PAGES

Length, in pages, of the process section.

VBN

Virtual block number, the number of the file's virtual block that is
mapped into the section's first page.

CLUSTER

Cluster size used when faulting pages into this process section.

REFCNT

Number of pages of this section that are currently mapped.

FLINK

Forward link, the pointer to the next entry in the PST list.

BLINK

Backward link, the pointer to the previous entry in the PST list.

FLAGS

Flags that describe the access that processes have to the process
section.

SYSTEM DUMP ANALYZER
SHOW PROCESS

The PO page table and Pl page table displays, also produced by the /PAGE_
TABLES qualifier, display listings of the process's page table entries in the
same format as that produced by the SHOW PAGE_TABLE command (see
Tables SDA-8 and SDA-9).
The process active channels display, the last produced by SHOW PROCESS
/ALL and the only one produced by the /CHANNEL qualifier, displays the
following information for each 1/0 channel assigned to the process:
Column

Contents

Channel

Number of the channel

Window

Address of the window control block (WCB) for
the file if the device is a file-oriented device; zero
otherwise

Status

Status of the device: "Busy" if the device has an
1/0 operation outstanding; blank otherwise

Device/file accessed

Name of the device and, if applicable, name of the
file being accessed on that device

The information listed under the heading "Device/file accessed" varies
from channel to channel and from process to process. SDA displays certain
information according to the conditions listed in Table SDA-12.
Table SDA-12

Process 1/0 Channel Information in the SHOW
PROCESS Display

Information Displayed 1

Type of Process

dcuu:

SDA displays this information for devices that
are not file structured, such as terminals, and for
processes that do not open files in the normal
way.

dcuu: filespec

SDA displays this information only if you are
examining a running system, and only if your
process has enough privilege to translate the
file-id into the fi/espec.

dcuu: (file-id) file spec

SDA displays this information only when you are
examining a dump. The filespec corresponds
to the file-id on the device listed. If you are
examining a dump from your own system, the
fi/espec is probably valid. If you are examining
a dump from another system, the fi/espec is
probably meaningless in the context of your
system.

1 This table uses the following formulas to identify the information displayed:

dcuu: (file-id) filespec
where:
dcuu: is the name of the device.
file-id is the RMS file identification.
filespec is the full file specification, including directory name.

SDA-131

SYSTEM DUMP ANALYZER
SHOW PROCESS

Table SDA-12 {Cont.)

Process 1/0 Channel Information in the
SHOW PROCESS Display

Information Displayed 1

Type of Process

dcuu:(file-id)

The file-id no longer points to a valid filespec,
as when you look at a dump from another
system; or the process in which you are running
SDA does not have enough privilege to translate
the file-id into the corresponding filespec

1This table uses the following formulas to identify the information displayed:

dcuu: (fife-id) fifespec
where:
dcuu: is the name of the device.
fife-id is the RMS file identification.
filespec is the full file specification, including directory name.

EXAMPLES

SDA> SHOW PROCESS

Process index: 001B
Process status:

Name: PUTP1

00044001

Extended PID: 27E0011B

RES,BATCH,PHDRES

PCB address
803C7710
PHD address
81F5C400
Master internal PID
00010018
Internal PID
0001001B
Extended PID
27E0011B
State
CUR 00
Current priority
3
Base priority
3
UIC
[00011 . 000176]
Mutex count
0
Waiting EF cluster
0
Starting wait time
1B001C1C
Event flag wait mask
BFFFFFFF
Local EF cluster 0
20000001
Local EF cluster 1
COOOOOOO
Global cluster 2 pointer 00000000
Global cluster 3 pointer 00000000

JIB address
806B9100
Swapfile disk address
02002FA1
Subprocess count
0
Creator internal PID
00000000
Creator extended PID
00000000
Termination mailbox
0000
AST's enabled
KES
AST's active
E
AST's remaining
39
12/12
Buffered I/O count/limit
Direct I/0 count/limit
18/18
BUFIO byte count/limit
31968/31968
# open files allowed left
90
Timer entries allowed left
9
Active page table count
0
Process WS page count
1020
Global WS page count
233

The SHOW PROCESS command displays information taken from the
software PCB of PUTPl, the SDA current process. According to the "State"
field in the display, process PUTPl is current on CPU 00 in the VMS
multiprocessing system.

SDA-132

SYSTEM DUMP ANALYZER
SHOW PROCESS
~

SHOW PROCESS/ALL

SDA>

Process index: OOAD
Process status:

Name: GLOBE

02040001

PCB address

Extended PID: 462002AD

RES,PHDRES
8044E650

JIB address

806E0010

Process header
First free PO address
Free PTEs between PO/P1
First free P1 address
Free page file pages
Page fault cluster size
Page table cluster size
Flags
Direct I/0 count
Buffered I/0 count
Limit on CPU time
Maximum page file count
Total page faults
File limit
Timer queue limit
Paging file index

0007D600
276902
7FEF2200
24234
16
0002
509
827
00000000
25600
7589
50
10
06000000

Accumulated CPU time
CPU since last quantum
Subprocess quota
AST limit
Process header index
Backup address vector
WSL index save area
PTs having locked WSLs
PTs having valid WSLs
Active page tables
Maximum active PTs
Guaranteed fluid WS pages
Extra dynamic WS entries
Locked WSLE counts array
Valid WSLE counts array

00000000
00000000
7FF9FB38
7FEF4AEC
7FFE9EOO

R2
R6
R10
PC
SSP

00000559
FFEE
8
50
0020
00003E12
00003980
5
20
21
26
20
698
1CD8
2564

Saved process registers
RO
R4
R8
AP
KSP

00000001
8044E650
00001F60
7FEF4AE4
= 7FFE7EOO

POBR = 82D43600

R1
R5
R9
FP
ESP

POLR = 000003EB

= 8000CA78
= 00000000
7FF9FA08
801622B4
7FFED04E

R3
R7
R11
PSL
USP

8044E6AO
00000003
7FFE0070
03COOOOO
7FEF4AE4

P1BR = 82654EOO

P1LR = 001FF792

80002398
00000000
7FF9FB38
7FFE9D58
7FFE9D58

R2
R6
R10
PC
SSP

R3
R7
R11
PSL
USP

0074
OOA6
OOB9
018C
0561

Current authorized working set size
Default (initial) working set size
Maximum working set allowed (quota)

Active registers for current process

------------------------------------

RO
R4
R8
AP
KSP

00000001
7FFA05AO
00001F60
7FFE9D70
7FFE7EOO

R1
R5
R9
FP
ESP

00000000
0007D400
7FF9FA08
801620A5
7FFED04E

00000000
00000010
7FFE0070
01400000
7FEF4AE4

Working set information

----------------------First WSL entry
First locked entry
First dynamic entry
Last entry replaced
Last entry in list

2048
512
2048

Working set list
INDEX

ADDRESS

STATUS

0074
0075
0076

7FFE7COO
7FFE7AOO
7FFE7800

VALID PROCESS WSLOCK
VALID PROCESS WSLOCK
VALID PROCESS WSLOCK

SDA-133

SYSTEM DUMP ANALYZER
SHOW PROCESS

Process section table information
Last entry allocated
First free PST entry

FFAO
0000

Process section table
INDEX ADDRESS PAGES

VBN

WINDOW

CLUSTER CHANNEL REFCNT FLINK BLINK

FFF8 00000200 OOOOOOOA 8082C400 00000002
FFFO 00001600 00000007 8082C400 OOOOOOOC
FFE8 00002400 00000012 8082C400 00000013

0 7FFCCFDO
0 7FFCCFDO
0 7FFCCFDO

10
0

FFE8
FFF8
FFFO

FLAGS

FFFO
FFE8
FFF8

WRT CRF

PO page table
ADDRESS

SVAPTE

PTE

TYPE PROT BITS PAGTYP

LDC STATE TYPE REFCNT

BAK

SVAPTE FLINK BLINK

-------- 1 NULL PAGE
00000200 82D43604 F9804F73 VALID UR
00000400 82D43608 F9806905 VALID UR
00000600 82D4360C F9807569 VALID UR

U PROCESS ACTIVE 07
U PROCESS ACTIVE 07
U PROCESS ACTIVE 07

00
00
00

0040FFF8
0040FFF8
0040FFF8

LDC STATE TYPE REFCNT

BAK

82D43604 0000 0153
82D43608 0000 0154
82D4360C 0000 0155

P1 page table
ADDRESS

SVAPTE

PTE

TYPE PROT BITS PAGTYP

7FEF2400 82E52C48 21800000 DZERO UW
7FEF2600 82E52C4C 21800000 DZERO UW
7FEF2800 82E52C50 21800000 DZERO UW

SVAPTE FLINK BLINK

U
U
U

Process active channels
Channel
0010
0020
0030
0040
0050
0060
0070
0080
0090
OOAO
OOBO

ooco

Window
00000000
8082C400
807F2260
00000000
00000000
807EFFEO
807EECCO
80838E80
807E4880
80818720
8083CFCO
8083DECO

Status

Device/file accessed
ROCK$DJA233:
ROCK$DJA233:(1008,48490,0)
LOVE$DUA200:(209,1,0)[V5COMMON.SYSLIB]SMGSHR.EXE;1 (section file)
VTA71:
VTA71:
LOVE$DUA200:(195,1,0)[V5COMMON.SYSLIB]LIBRTL.EXE;1 (section file)
LOVE$DUA200:(199,1,0)[V5COMMON.SYSLIB]MTHRTL.EXE;1 (section file)
LOVE$DUA200: (196,1,0)[V5COMMON.SYSLIB]LIBRTL2.EXE;1
LOVE$DUA200: (210,1,0)[V5COMMON.SYSLIB]SORTSHR.EXE;1
LOVE$DUA200:(191,1,0)[V5COMMON.SYSLIB]FDLSHR.EXE;1
LOVE$DUA200:(169,1,0)[V5COMMON.SYSLIB]CONVSHR.EXE;1
ROCK$DJA233:(1026,16,0)

The SHOW PROCESS/ ALL command displays information taken from the
software PCB of process GLOBE, and then proceeds to display the process
header, the process's registers, the process section table, the PO page table, the
Pl page table, and information about the 1/0 channels owned by the process.
These displays may also be obtained by the /PCB, /PHD, /REGISTERS,
/PROCESS_SECTION_TABLE, /PO, /Pl, and /CHANNEL qualifiers,
respectively.

SDA-134

SYSTEM DUMP ANALYZER
SHOW PROCESS

SDA>

SHOW PROCESS/LOCKS/INDEX=OA

Process index: OOOA

Name: JOB_CONTROL

Extended PID: 4620010A

Lock data:
Lock id: 09960AOF
VALBLK CONVERT SYNCSTS
PID:
0001000A
Flags:
Par. id: 00000000
SYSTEM
Granted at
PW
Sublocks:
100
LKB:
8082BOEO
BLKAST
Resource:
003C0248 24534052
RMS$H. <. Status: ASYNC
Length
26
444B4C4F 46020000
... FOLKD
Exec. mode
00202020 20202024
$
System
00000000 00000000
Local copy
Lock id: 043C0491
PID:
0001000A
Flags:
NO QUEUE
Par. id: 00000000
Granted at
EX
Sublocks:
0
LKB:
8083FAEO
BLKAST
Resource:
4C41434F 2443424A
JBC$ROCK Status:
10
00000000 00002041
A ..... .
Length
User mode
00000000 00000000
System
00000000 00000000
Local copy

The SHOW PROCESS /LOCKS /INDEX=OA command displays information
about the locks held by process JOB_CONTROL, whose PCB is at index OA
into the system's PCB list. This command implicitly makes JOB_CONTROL
the SDA current process for subsequent commands that display process
context information. It has no effect on SDA CPU context as JOB_CONTROL
is not current on any processor in the VMS multiprocessing system.

SDA-135

SYSTEM DUMP ANALYZER
SHOW PROCESS

SDA> SHOW RMS

RMS Display Options: IFB,IRB,IDX,BDB,BDBSUM,ASB,CCB,WCB,FCB,FAB,RAB,NAM,XAB,RLB,
BLB,BLBSUM,GBD,GBH,FWA,GBDSUM,JFB,NWA,RU,DRC,SFSB,GBSB
Display RMS structures for all !FI values.
SDA> SHOW PROCESS/RMS

Process index: 0032

Name: BEASSEM_MTHRTL_

IFAB Address: 7FF9C808

IF!: 0002

Extended PID: 27200132

Organization: Sequential

-----------PRIM_DEV:
BKPBITS:
BLN:
EFN:
IDS:
IOS2:
IOS4:
ATJNLBUF:
FSBPTR:
SHR:
IRAB_LNK:
FAC:
ORGCASE:
LAST_FAB:
!FI:
FWA_pTR:
BDB_FLNK:
BDB_BLNK:
RFMORG:
RAT:
LRL:
FFB:
FSZ:
DEQ:
HBK:
EBK:
LAST_GOOD_EBK:
RNS_LEN:
SFSB_PTR:
GBSB_pTR:
PAR_LOCK_ID:
AS_DEV:
ASDEVBSIZ:
GBH_PTR:
BI_JFB:
JOURNAL:
RUSB_LNK:
RUFB_LNK:
ATJNLBUF:
JNLFLG:
RECVRFLGS:
JNLFLG2:
EXTJNLBUF:

1C4D4108
DIR,FOD,SHR,AVL,ELG,IDV,ODV,RND
00080020
ACCESSED,NORECLK
3A
58.
BID:
OB
11.
00
MODE:
03
00000001
ASBADDR:
00000000
WAIT_Q_FLINK:
0000
00000000
00000000
ARGLST:
7FF21418
WAIT_Q_BLINK:
00000000
00000000
00000000
AGENT_MODE:
03
02
SHRGET
7FF9C958
CHNL:
ooco
02
GET
00
Sequential
NWA_PTR:
00081FDO
00000000
0002
ECHO_ISI:
0000
7FF9CCOO
7FF9CBBO
DEVBUFSIZ:
00000200
7FF9CB60
RTDEQ:
0000
02
VAR
02
CR
76.
HBK_DISK:
004C
ooocoooo
132.
EBK_DISK:
0084
ooocoooo
00
0.
BKS:
00
0.
0000
MRS:
0000
12.
oooooooc
GBC:
0000

FAB Address:

00081FDO

BID:
BLN:
!FI:
FOP:
STS:
STV:
FAC:
SHR:
CTX:
ORG:
RAT:

03
50
0002
00000000
00010001

-----------

SDA-136

oooooooc

LAST_GOOD_FFB:
LOCK_BDB:
AVLCL:
AVGBPB:

0000
00000000
0003
0000

BLBFLNK:
BLBBLNK:
AI_JFB:
AT_JFB:
BUFFER_OFFSET:
RU_ACTIVE:
RU_HANDLE:
JNLBDB:

00000000
00000000
00000000
00000000
0000
00
00000000
00000000

RLB FL FLINK.

7FF9C858

ooooooco

ALQ:
DEQ:

oooooooc

02
GET
02
SHRGET
00000000
00
Sequential
02
CR

RTV:

00000000
00000000
00000000
00000000
00000000
1C4D4108
00000200
00000000
00000000
00
00000000
00000000
00000000
00
00
00
00000000

3.
80.

0000

512.
0.

0.
0.
0.
0.
3.
0.

0.
0.

SYSTEM DUMP ANALYZER
SHOW PROCESS

RFM:
JOURNAL:
RU_FACILITY:
XAB:
FNA:
FNS:
File name:
MRS:
BLS:
FSZ:
SDC:
ACMODES:

02
VAR
00
00
0008235C
NAM:
000822DO
00062894
DNA:
00000000
2B
DNS:
00
VMSTESTRESD$: [MTHRTL.SRC]MTH$ATAN2TST.B32;1
0000
MRN :
00000000
0200
512.
BKS:
00
00
0.
DEV:
4108
1C4D4108
GBC:
0000
00

XABFHC Address: 0008235C

--------------COD:
NXT:
RFD:
ATR:
LRL:
HBK:
EBK:
MRZ:
GBC:
SBN:

29.

00082330
02
02
CR
004C

76.

oooooooc
oooooooc
0000
0000
00000000

0.
0.

BLN:
RVN:

2C
0202

FFB:
HSZ:
DXQ:

0084
00
0000

BLN:
RVN:

2C
0002

44.

XABDAT Address: 00082330

---------------

COD:
NXT:
RDT:

12
00000000

18.

44.

CDT:
RDTO:
RDT4:

2AB640EO
008F8F1B

EDT:

CDTO:
CDT4:

69508580
008F8EEA

BDTO:
BDT4:

00000000
00000000

BDT:
EDTO:
EDT4:

00000000
00000000

NAM Address:

000822DO

----------BID:
BLN:
NOP:

wee

FNB:

02
60
00
00000000
002030C7

2.
96.

RFS:

NO_RFS

PPF,NODE,QUOTED,GRP_MBR,WILD_DIR,
DIR_LVLS,WILD_UFD,WILD_SFD1,WILD_SFD3.WILD_SFD5
Expanded String:
ESL: 2B / ESS: FF © ESA: 00091A98
VMSTESTRESD$:[MTHRTL.SRC]MTH$ATAN2TST.B32;1
Resultant String:
RSL: 2B I RSS: FF © RSA: 00091A98
VMSTESTRESD$:[MTHRTL.SRC]MTH$ATAN2TST.B32;1
FID:
[1CA4 ,0003. 0001]
NODE:
00/00091A98
DEV:
OD/00091A98
VMSTESTRESD$:
DIR:
OC/00091AA5
[MTHRTL. SRC]
NAME:
OC/00091AB1
MTH$ATAN2TST
TYPE:
04/00091ABD
.B32
VER:
02/00091AC1
;1
CCB Address: 7FFCAD30
-----------

UCB:
STS:
AMOD:
DIRP:

80487E70
00
02
00000000

WIND:

80B7A1CO

IOC:

0001

SDA-137

SYSTEM DUMP ANALYZER
SHOW PROCESS

WCB Address: 80B7A1CO

-----------

WLFL:
WLBL:
ACCESS:
PID:
ACON:
NMAP:
RVT:
READS:
STVBN:
P1_LBN:
P2_LBN:

804A2AAO
804A2AAO
01
READ
00010032
0001
NOWRITE
0005
808F9140
00000001
00000001
010C568E
010C5695

SIZE:
TYPE:

0060
12

ORGUCB:

80487E70

FCB:
LINK:
WRITES:
PL COUNT:
P2_COUNT:

804A2A90
00000000
00000000
0003
0001

SIZE:
TYPE:
WLFL:
ACNT:
LCNT:
ACCLKMODE:

OODO
07
80B7A1CO
0001
0001
03

STVBN:
STLBN:
EFBLK:
DIRINDX:
ACCLKID:
TRUNCVBN:
HIGHWATER:
HWM_PARTIAL:
HWM_WAITFL:

00000001
00000000

00000000
00283A1F
00000000
OOOOOOOD
0000
804A2AF8

HWM_WAITBL:

804A2AF8

ACMODE:

FFFFFFFF /FFFFFFFF

FCB Address: 804A2A90

----------FCBFL:
FCBBL:
EXFCB:
REFCNT:
WCNT:
TCNT:
STATUS:
SEGN:
HDLBN:
FILESIZE:
VERSIONS:
DIRSEQ:
LOCKBASIS:
CACHELKID:
HWM_UPDATE:
HWM_ERASE:
FID:

804BFBFO
804788AO
00000000
0001
0000
0000
0000
0000
OOOOCE22

1.
0.
0.
0.

oooooooc

0000
0.
0000
01001CA4
00000000
0000
0.
0000
0.
[1CA4, 0003, 0001]

1.
1.

oooooooc

ORB
FILEOWNER:
SYS_PROT:
OWN_PRDT:
GRP_PRDT:
WOR_PROT:
ACLFL:
ACLBL:

[007F, 0009]
OOOOEEOC
00000000
00000000
00000000
00000000
00000000

FWA Address: 7FF9CCOO

-----------

FLAGS:

20C7F810
06000003

PASSFLGS:
FLDFLGS:
FLDFLGS:
PARSEFLGS:
DIRFLGS:
DIRWCFLGS:
LNFLGS:
SLFLGS:

10
F8
C7
20
03
00
00
06

DIRTERM:
ESCSTRING:
ESCTYP:
BUFFLG:
XLTMODE:
XLTBUFF1:
DEVBUFSIZ:

5D
"]"
00000000
00
0.
00
03
7FF9D600
00000000

SDA-138

FNA_PASS
VERSION,TYPE,NAME,DIR,DEVICE
EXP_VER,EXP_TYPE,EXP_NAME,EXP_DIR,EXP_DEV
DIR1,DIR2
CONCEAL_DEV,ROOT_DIR
ROOTERM:
ESCFLG:
ESCIFI:
DIRBDB:
XLTSIZE:
XLTBUFF2:
DEV_CLASS:

5D
"]"
00
0000
00000000
oooc
12.
7FF9D700
00000001

SYSTEM DUMP ANALYZER
SHOW PROCESS

FIB:

00000040 / 7FF9CDF4
FIB fields within the FWA:
WSIZE:
ACCTL:
FID:
NUMCTL:
EXCTL:
CNTRLFUNC:
EXSZ:
EXVBN:
ALOPTS:
VERLIMIT:
STATUS:
ALT _ACCESS:

UIC:
DEVNODADR:
LEVEL:
DIRLEN:
SWB_PTR:
SLBH_PTR:
SLBH_FLINK:
ITM_INDEX:
ITM_ATTR:
ITM_STRING:
ITM_MAX_INDEX:
ITM_END:
LOGNAM:
DIR:
NODE:
DEVICE:
CONCEAL_DEV:
CDIR1:
CDIR2:
CDIR3:
CDIR4:
CDIR5:
CDIR6:
CDIR7:
CDIR8:
DIR1:
DIR2:
DIR3:
DIR4:
DIR5:
DIR6:
DIR7:
DIR8:
NAME:
TYPE:
RNS:
VERSION:
SHRFIL:
AS_SHRFIL:
SHRFIL_LCK:
NODE!:
NODE2:
NODE3:
NODE4:
NODE5:
NODE6:
NODE7:
NODE8:

0.
wee :
00000000
00
00000001
NOWRITE
DID:
(148B, 0002, 0001)
(1CA4 ,0003. 0001)
0000
0000
REWIND FIL
0000
CNTRLVAL:
00000000
00000000
00000000
ALALIGN:
00
00
ACLCTX:
00000000
7FFF
00000000
00000000

[0,0)
LOOKUP:
00000000
7FFE03FO
PRO:
0000
0000
03
3.
UCHAR:
00
0.
OB
11.
SUBNODCNT:
00000000
SLB_PTR:
7FF9C8F8
7FF9C8F8
7FF9C8F8
SLBH_BLINK:
7FF9C938
00010004 I 7FF9CCC4 I 00000000
00030004 I 7FF9CCCC I 00000000
000200FF I 7FF9D600 I 7FF9CC9E
00070004 I 7FF9CCC8 I 00000000
00000000
OOOOOOOB / 7FF9D600 .......... .
00000030 / 7FF9D468 SRCRTLTDUA101 .................................. .
00000000 I 7FF9D3E9
OOOOOOOB I 7FF9D1E9 $254$DUA101
OOOOOOOC / 7FF9D2E8 VMSTESTRESD$
00000007 / 7FF9CF7E VMSTEST
00000000 I 7FF9CFA5
00000000 I 7FF9CFCC
00000000 I 7FF9CFF3
00000000 I 7FF9D01A
00000000 I 7FF9D041
00000000 I 7FF9D068
00000000 I 7FF9D08F
00000006 I 7FF9CE46 MTHRTL
00000003 I 7FF9CE6D SRC
00000000 I 7FF9CE94
00000000 I 7FF9CEBB
00000000 I 7FF9CEE2
00000000 I 7FF9CF09
00000000 I 7FF9CF30
00000000 I 7FF9CF57
00000012 I 7FF9DOB6 MTH$ATAN2TST.B32;1
00000003 I 7FF9DOC3 B32
0000012E / 7FF9DOB6 MTH$ATAN2TST.B32;1
00000001 I 7FF9DOC7 1
oooooooc I 7FF9D498 _$254$DUA101
oooooooc I 7FF9D4B8 _$254$DUA101
00000010 I 7FF9D4A8 .RES28JUN
00000000 I 00000000
00000000 I 00000000
00000000 I 00000000
00000000 I 00000000
00000000 I 00000000
00000000 I 00000000
00000000 I 00000000
00000000 I 00000000

BI Journaling ACE:
(UNKNOWN=%XOO,SIZE=%DO,FLAGS=%XOOOO,ACCESS=%XOOOOOOOO,DATA)
AI Journaling ACE:
(UNKNOWN=%XOO,SIZE=%DO,FLAGS=%XOOOO,ACCESS=%XOOOOOOOO,DATA)
AT Journaling ACE:
(UNKNOWN=%XOO,SIZE=%DO,FLAGS=%XOOOO,ACCESS=%XOOOOOOOO,DATA)
RU Journaling ACE:
(UNKNOWN=%XOO,SIZE=%DO,FLAGS=%XOOOO,ACCESS=%XOOOOOOOO,DATA)

SDA-139

SYSTEM DUMP ANALYZER
SHOW PROCESS

IRAB Address: 7FF9C958

!SI: 0001

-----------IFAB_LNK:
BKPBITS:
BLN:
EFN:
IDS:
IOS4:
IRAB_LNK:
LAST_RAB:
JNLBDB:
RLB_FLINK:
RLB_BLINK:
!SI:
JNLFLG:
ATJNL_PTR:
RP_VBN:
RP_OFF:
CURVBN:
CACHEFLGS:
SRCHFLAGS:
SPL_BITS:
STOPLEVEL:
POS_INS:
LST_REC:
SPLIT_!:
OWNER_ID:
OWN_ISI:
RU_HANDLE:
PPF _ISI:
MBC_P1:
TEMPO:
ROVHDSZ:
PRE_CCTL:
CURBLKADR:
ENDBLKADR:
PPF_STR:

7FF9C808
00000400
27
00
00000000
00000000
00000000
00081DA4
00000000
7FF9C99C
7FF9C99C
0001
00
00000000
00000000
00000000
00000000
01
0000
00
00
0000
00000000
0000
00010000
0001
00000000
01

RAB Address:

00081DA4

BID:
BLN:
ROP:
CTX:
STS:
STV:
TMO:
USZ:
RSZ:
KBF:
PBF:
KRF:
MBF:
FAB:
XAB:

01
44
00010600
00000000
00000000
00010001
00
0084
0000
00000000
00000000
00
00
00081FDO
00000000

ASB Address:

7FF9CAOO

-----------

ARGCNT: 00
ARGLST: 00000000
FABRAB: 00000000
ERR:
00000000
SUC:
00000000
R6:
R7:
RS:
R10:
R11:

00000000
00000000
00000000
00000000
00000000

SDA-140

0.
0.
0.
LOCK
0.
0.
0.
1.
1.

BID:
MODE:
ASBADDR:
ARGLST:
CURBDB:
NXTBDB:

OA
03
7FF9CAOO
7FF21418
00000000
7FF9CBBO

10.

WAIT _Q_FLINK:
WAIT_Q_BLINK:
!DENT:

00000000
00000000
00000230

NRP_VBN:
NRP_OFF:

00000001
00000000

1.
0.

SPLIT:
PRT_VBN:
SPLIT_2:
BCNT:
MBC:
MBF:
OWN_ID:

0000
00000000
0000
03
OB
03
0000

0.
0.
0.
3.
11.
3

CSIZ:
RTOTLSZ:
POST_CCTL:
PPF_STRLEN:

0000
0000
00
0000

0.
0.
0.

12.

00000000
0000
00
00000000
00000000
00000000

-----------

RAHWBH
39.

0.
0.

..............

1.
!SI:
68.
RAH,WBH,LOC
RAC:
RFA:

0001

0.
132.
0.

00000000
00091F38
00000000
00
00
00
00000000
00000000

0.
0.

00
SEQ
00000000 ' 0000

RHB:
UBF:
RBF:
KSZ:
PSZ:
MBC:
BKT:
DCT:

0.
BID:
BLN:
STKLEN:
STKSIZ:

OD
44
OOEO
0000

13.
68.
224.
0.

0.
0.
0.

SYSTEM DUMP ANALYZER
SHOW PROCESS

Saved Stack:
SP =>

(STACK IS EMPTY)
BDB/GBPB Summary

Address USERS SIZE
7FF9CBBO
7FF9CB10
7FF9CB60

NUMB

BLB_PTR

VBN

ADDR

0 6144 6144 00000001 00000000 7FFAOCOO
0 6144
0 00000000 00000000 7FF9DCOO
0 6144
0 00000000 00000000 7FF9F400
3. BDBs were processed
0. GBPBs were processed

BDB Address:

7FF9CBBO

FLINK:
BLINK:
FLGS:
USERS:
CACHE_ VAL:
SIZE:
ADDR:
VBNSEQNO:
WK1:
REL_VBN:
ASB:
ALLOC_ADDR:
ALLOC_SIZE:
VAL_VBNS:
IDSB:

7FF9CB10
7FF9C850
04
!OP
0000
00

1800
7FFAOCOO
00000000
00000000
00
00000000
7FFAOCOO
1800
00

REUSE_COUNT:

00000000
00000000
00000000

BDB Address:

7FF9CB10

FLINK:
BLINK:
FLGS:
USERS:
CACHE_ VAL:
SIZE:
ADDR:
VBNSEQNO:
WK1:
REL_VBN:
ASB:
ALLOC_ADDR:
ALLOC_SIZE:
VAL_VBNS:
IDSB:

7FF9CB60
7FF9CBBO

REUSE_COUNT:

0.
0.

6144.

6144
0.

VAL

FLGS

0
0
0

BDB
BDB
BDB

!OP

BID:
BLN:

BLB_PTR:
BUFF_ID:
NUMB:
VBN:
WAIT:
CURBUFADR:
PRE_CCTL:

00000000
0000
1800
00000001
00000000
00000000

BI_BDB:
AI_BDB:
POST_CCTL:
WAIT_Q_FLINK:
WAIT_Q_BLINK:

00000000
00000000
00
00000000
00000000

BID:
BLN:

BLB_PTR:
BUFF_ID:
NUMB:
VBN :
WAIT:
CURBUF ADR:
PRE_CCTL:

00000000
0000
0000
00000000
00000000
00000000
00

BI_BDB:
AI_BDB:
PDST_CCTL:
WAIT_Q_FLINK:
WAIT_Q_BLINK:

00000000
00000000
00
00000000
00000000

12.
20.

6144.

12.
20.

0000
00

1800
7FF9DCOO
00000000
00000000
00

00000000
7FF9DCOO
1800
00

00000000
00000000
00000000

0.
0.

6144.

6144
0.

0.
0.

SDA-141

SYSTEM DUMP ANALYZER
SHOW PROCESS

BDB Address:

7FF9CB60

FLINK:
BLINK:
FLGS:
USERS:
CACHE_ VAL:
SIZE:
ADDR:
VBNSEQNO:
WK1:
REL_VBN:
ASB:
ALLOC_ADDR:
ALLOC_SIZE:
VAL_VBNS:
IDSB:

7FF9C850
7FF9CB10
00
0000
00
1800
7FF9F400
00000000
00000000
00
00000000
7FF9F400
1800
00
00000000
00000000
00000000

-----------

REUSE_COUNT:

o.
0.
6144.

0.
6144
0.

BID:
BLN:

OC
14

BLB_PTR:
BUFF_ID:
NUMB:
VBN:
WAIT:
CURBUFADR:
PRE_CCTL:

00000000
0000
0000
00000000
00000000
00000000
00

BI_BDB:
AI_BDB:
POST_CCTL:
WAIT_Q_FLINK:
WAIT_Q_BLINK:

00000000
00000000
00
00000000
00000000

12.
20.
0.
0.

The SHOW PROCESS /RMS command displays those RMS data structures
associated with the image files process GLOBE, the SDA current process, is
accessing.

SDA-142

SYSTEM DUMP ANALYZER
SHOW RESOURCE

SHOW RESOURCE
Displays information about all resources in the system, or about a resource
associated with a specific lock.

FORMAT

SHOW RESOURCE

PARAMETERS

None.

QUALIFIERS

/ALL

/ALL
}
{ /LOCKID=lock-id

Displays information from all resource blocks (RSBs) in the system. This is
the default behavior of the SHOW RESOURCE command.

/LOCKID=lock-id
Displays information on the resource associated with the lock with the
specified lock-id.

DESCRIPTION

The SHOW RESOURCE command displays the information listed in
Table SDA-13 for each resource in the system or the specific resource
associated with the specified lock-id.
Table SDA-13

Resource Information in the SHOW RESOURCE
Display

Field

Contents

Address of RSB

Address of the resource block (RSB) that
describes this resource.

Parent RSB

Address of the RSB that is the parent of this
RSB. This field is 00000000 if the RSB itself is a
parent block.

Sub-RSB count

Number of RSBs of which this RSB is the parent.
This field is 0 if the RSB has no sub-RSBs.

SDA-143

SYSTEM DUMP ANALYZER
SHOW RESOURCE

Table SDA-13 (Cont.)

Resource Information in the SHOW
RESOURCE Display

Field

Contents

Group grant mode

Indication of the most restrictive mode in which
a lock on this resource has been granted. This
field can contain the following values (shown in
order from the least restrictive mode to the most
restrictive):

Value

Meaning

Null mode

Concurrent-read mode

Concurrent-write mode

Protected-read mode

Protected-write mode

Exclusive mode

For information on conflicting and incompatible
lock modes, see the VMS System Services
Reference Manual.

SDA-144

Conversion grant mode

Indication of the most restrictive lock mode to
which a lock on this resource is waiting to be
converted. This does not include the mode for
which the lock at the head of the conversion
queue is waiting.

BLKAST count

Number of locks on this resource that have
requested a blocking AST.

Value block

Hexadecimal dump of the 16-byte block value
block associated with this resource.

Sequence#

Sequence number associated with the resource's
value block. If the number indicates that the value
block is not valid, the words "Not valid" appear
to the right of the number.

CSID

Cluster system identification number (CSID) of the
node that owns the resource

Resource

Dump of the name of this resource, as stored at
the end of the RSB. The first two columns are
the hexadecimal representation of the name,
with the least significant byte represented
by the rightmost two digits in the rightmost
column. The third column contains the ASCII
representation of the name, the least significant
byte being represented by the leftmost character
in the column. Periods in this column represent
values that correspond to nonprinting ASCII
characters.

Length

Length in bytes of the resource name.

SYSTEM DUMP ANALYZER
SHOW RESOURCE

Table SDA-13 (Cont.)
Field

Resource Information in the SHOW
RESOURCE Display
Contents
Processor mode of the name space in which this
RSB resides.
Owner of the resource. Certain resources, owned
by the VMS operating system, list "System" as
the owner. Locks owned by a group have the
number (in octal) of the owning group in this field.

Granted queue

List of locks on this resource that have been
granted. For each lock in the list, SDA displays
the number of the lock and the lock mode in
which the lock was granted.

Conversion queue

List of locks waiting to be converted from one
mode to another. For each lock in the list, SDA
displays the number of the lock, the mode in
which the lock was granted, and the mode to
which the lock is to be converted.

Waiting queue

List of locks waiting to be granted. For each lock
in the list, SDA displays the number of the lock
and the mode requested for that lock.

EXAMPLES
[I

SDA> SHOW RESOURCE
Resource database
Address of RSB: 807F6120 Group grant mode:
NL
Parent RSB:
806EA180 Conversion grant mode: NL
Sub-RSB count:
0
0 BLKAST count:
Value block:
806CE510 00000000 00000002 00000002
Seq. #: 00000008
Resource:
09ED7324 42313146
F11B$s.
10
00000000 00000200
........
CSID: 00020041
Length
........
Kernel mode
00000000 00000000
00000000 00000000
........
System
Granted queue (Lock ID I Gr mode):
006801AE NL
Conversion queue (Lock ID I Gr/Rq mode):
*** EMPTY QUEUE ***
Waiting queue (Lock ID I Rq mode):
*** EMPTY QUEUE ***
Address of RSB: 807EB9EO Group grant mode:
PW
Parent RSB:
00000000 Conversion grant mode: EX
Sub-RSB count:
0 BLKAST count:
1
Value block:
00000000 00000003 00000000 OOOOFFF2
Seq. #: 0000027F Not valid
Resource:
32245F24 44414853
SHAD$_$2
Length
16
3A31534A 44243435
54$DJS1:
CSID: 0002001A
Kernel mode
00000000 00000000
........
System
00000000 00000000
........
Granted queue (Lock ID I Gr mode):
00020301 CR

SDA-145

SYSTEM DUMP ANALYZER
SHOW RESOURCE

Conversion queue (Lock ID I Gr/Rq mode):
095BOOF2 PW/EX
Waiting queue (Lock ID I Rq mode):
054400BC EX

The SHOW RESOURCE command displays information taken from the RSBs
of all resources in the system. For instance, the RSB at 807EB9E0 16 is a
parent block with no sub_RSBs. The most restrictive lock granted on this
resource is in protected-write (PW) mode. There is a lock on the conversion
queue waiting to be converted from PW mode to exclusive (EX) mode.
~

SDA>

SHOW PROCESS/LOCKS

Process index: 001C

Name: STARTQ

Extended PID: 4800011C

Lock data:
Lock id: 0117054F
PID:
0001001C
VALBLK SYNCSTS SYSTEM
Flags:
Par. id: 00000000
Granted at
PW
NOQUOTA
Sublocks:
0
LKB:
808091AO
Resource:
45527624 42313146
F11B$vRE Status: NOQUOTA
20205241 4D323053
Length
18
S02MAR
Kernel mode
00000000 00002020
System
00000000 00000000
Process copy of lock 008209CF on system 0002001

SDA> SHOW RESOURCE/LOCKID=117054F
Resource database
Address of RSB: 806BB050 Group grant mode:
NL
Parent RSB:
00000000 Conversion grant mode: NL
Sub-RSB count:
4 BLKAST count:
0
Value block:
00960102 0000330B 000735AA 5A020005
Seq. #: 00006D9F
Resource:
45527624 42313146
F11B$vRE
Length
18
20205241 4D323053
S02MAR
CSID: 0002001A
Kernel mode
00000000 00002020
System
00000000 00000000
Granted queue (Lock ID I Gr mode):
0117054F PW
00060545 CR
Conversion queue (Lock ID I Gr/Rq mode):
*** EMPTY QUEUE ***
Waiting queue (Lock ID I Rq mode):
*** EMPTY QUEUE ***

The SHOW PROCESS/LOCKS command lists all locks associated with the
SDA current process, STARTQ. Its display is identical to that of the
SHOW LOCK command, illustrated in Table SDA-7. The SHOW
RESOURCE/LOCKID=l 17054F command determines that this particular
lock is on the granted queue in protected-write mode for the resource at
806BB05016·

SDA-146

SYSTEM DUMP ANALYZER
SHOW RMS

SHOW RMS
Displays the RMS data structures selected by the SET RMS command to
be included in the default display of the SHOW PROCESS/RMS command.

FORMAT

SHOW RMS

PARAMETERS

None.

QUALIFIERS

None.

DESCRIPTION

The SHOW RMS command lists the names of the data structures selected for
the default display of the SHOW PROCESS /RMS command.
For a description of the significance of the options listed in the SHOW RMS
display, see the description of the SET RMS command and Table SDA-6.
For an illustration of the information displayed by the SHOW
PROCESS /RMS command, see the examples included in the description of
the SHOW PROCESS command.

EXAMPLES

SDA>

SHOW RMS

RMS Display Options: IFB,IRB,IDX,BDB,BDBSUM,ASB,CCB,WCB,FCB,FAB,RAB,NAM,XAB,RLB,
BLB,BLBSUM,GBD,GBH,FWA,GBDSUM,JFB,NWA,RU,DRC,SFSB,GBSB
Display RMS structures for all !FI values.

The SHOW RMS command displays the full set of options available for
display by the SHOW PROCESS /RMS command. SDA, by default, selects
the full set of RMS options at the beginning of an analysis.
~

SDA>
SDA>

SET RMS=(IFAB,CCB,WCB)
SHOW RMS

RMS Display Options: IFB,CCB,WCB
Display RMS structures for all !FI values.

The SET RMS command establishes the IFB, CCB, and WCB as the structures
to be displayed when the SHOW PROCESS /RMS command is issued. The
SHOW RMS command verifies this selection of RMS options.

SDA-147

SYSTEM DUMP A·NALYZER
SHOW RSPID

SHOW RSPID
Displays information about response IDs (RSPIDs) of all SCS connections
or, optionally, a specific SCS connection.

FORMAT

SHOW RSPID

PARAMETERS

None.

QUALIFIER

/CONNECTION=cdt-address

[/CONNECTION=cdt-address]

Displays RSPID information for the specific SCS connection whose connection
descriptor table (CDT) address is provided in cdt-address. 15

DESCRIPTION

Whenever a local system application (SYSAP) requires a response from
a remote SYSAP, a unique number, called an RSPID, is assigned to the
response by the local system. The RSPID is transmitted in the original
request (as a means of identification), and the remote SYSAP returns the
same RSPID in its response to the original request.
The SHOW RSPID command displays information taken from the response
descriptor table (RDT), which lists the currently open local requests that
require responses from SYSAPs at a remote node. For each RSPID, SDA
displays the following information:

•

RSPID value

•

Address of the class driver request packet (CDRP) which generally
represents the original request

•

Address of the CDT that is using the RSPID

•

Name of the local process using the RSPID

•

Remote node from which a response is required (and has not yet been
received).

SDA-148

SYSTEM DUMP ANALYZER
SHOW RSPID

EXAMPLES

SDA> SHOW RSPID
VAXcluster data structures
Summary of Response Descriptor Table(RDT) 8037A4A8 --RSPID
04C30000
06260001
OC390002

CDRP Address

CDT Address

Local Process Name

Remote Node

80391780
80804FAO
807E0460

8037AB50
8037AF10
8037AD30

VMS$DISK_CL_DRVR
VMS$VAXcluster
VMS$VAXcluster

SOWHAT
WALK IN
OLEO

The SHOW RSPID command shows the response IDs that are currently open
for all local connections in the VAXcluster.

SDA> SHOW RSPID/CONNECTION=G37B7DO
VAXcluster data structures
Summary of Response Descriptor Table(RDT) 8037A4A8 --RSPID
08B8001C
09150010

CDRP Address

CDT Address

Local Process Name

Remote Node

807F0300
807F08AO

8037B7DO
8037B7DO

VMS$VAXcluster
VMS$VAXcluster

METEOR
METEOR

The SHOW RSPID /CONNECTION=G37B7DO command displays only those
RSPIDs in use that are associated with the SCS connection whose CDT is at
address 8037B7D016·

SDA-149

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

SHOW SPINLOCKS
Displays information taken from the data structures that provide system
synchronization in a VMS multiprocessing environment.

FORMAT

SHOW SPINLOCKS [/OWNED] [/BRIEF

/FULL

/DYNAMIC
[ /STATIC
name
i
/ ADDRESS=expression J
[ /INDEX=expression

PARAMETER

QUALIFIERS

name
Name of the spin lock, fork lock, or device lock structure to be displayed.
You can obtain the names of the static system spin locks and fork locks
from Table SDA-14. Device lock names are of the form [node$]lock, where
node optionally indicates the VAXcluster node name (allocation class)
and lock indicates the device and controller identification (for example,
HAETAR$DUA).

/ ADDRESS=expression
Displays the lock at the address specified in expression. You can use the
/ADDRESS qualifier to display a specific device lock; however the name of
the device lock is listed as "Unknown" in the d~splay.

/BRIEF
Produces a condensed display of the lock information displayed by default
by the SHOW SPINLOCKS command, including the following: address, spin
lock name or device name, IPL or device IPL, rank, index, ownership depth,
number of waiting CPUs, CPU ID of the owner CPU, and interlock status
(depth of ownership).

/DYNAMIC
Displays information for all device locks in the system.

/FULL
Displays full descriptive and diagnostic information for each displayed spin
lock, fork lock, or device lock.

/IN DEX=expression
Displays the system spin lock whose index is specified in expression. You
cannot use the /INDEX qualifier to display a device lock.

SDA-150

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

/OWNED
Displays information for all spin locks, fork locks, and device locks owned
by the SDA current CPU. If a processor does not own any spin locks, SDA
displays the following message:
No spinlocks currently owned by CPU xx

xx represents the CPU ID of the processor.

/STATIC
Displays information for all system spin locks and fork locks.

DESCRIPTION

The SHOW SPINLOCKS command displays status and diagnostic information
about the VMS multiprocessing synchronization structures known as spin
locks.
A static spin lock is a spin lock the data structure for which is permanently
assembled into the system. Static spin locks are accessed as indexes into a
vector of longword addresses called the spin lock vector, the address of which
is contained in SMP$AR_SPNLKVEC. System spin locks and fork locks are
static spin locks. Table SDA-14 lists the static spin locks.

Iii,

A dynamic spin lock is a spin lock that is created based on the configuration of
a particular system. One such dynamic spin lock is the device lock SYSGEN
creates when configuring a particular device. This device lock synchronizes
access to the device's registers and certain UCB fields. VMS creates a dynamic
spin lock by allocating space from nonpaged pool, rather than assembling the
lock into the system as it does in creating a static spin lock.
See the VMS Device Support Manual for a full discussion of the role of spin
locks in maintaining synchronization of kernel mode activities in a VMS
multi processing environment.

Table SDA-14

Static Spin Locks

Name

Description

QUEUEAST

Fork lock for queuing ASTs at IPL 6

FILSYS

Lock on file system structures

IOLOCK8

Fork lock for executing a driver fork process at IPL 8

PR_LK8

Primary CPU's private lock for IPL 8

TIMER

Lock for adding and deleting timer queue entries and searching the timer queue

JIB

Lock for manipulating job nonpaged pool quotas as reflected by the fields JIB$L_BYTCNT
and JIB$L _BYTLM in the job information block (JIB)

MMG

Lock on VMS memory management, PFN database, swapper, modified page writer, and
creation of per-CPU database structures

SCH ED

Lock on process control blocks (PCBs), scheduler database, and mutex acquisition and
release structures

IOLOCK9

Fork lock for executing a driver fork process at IPL 9

PR_LK9

Primary CPU's private lock for IPL 9

IOLOCK10

Fork lock for executing a driver fork process at IPL 10

PR_LK10

Primary CPU's private lock for IPL 10

SDA-151

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

Table SDA-14 {Cont.)

Static Spin Locks

Name

Description

IOLOCK11

Fork lock for executing a driver fork process at IPL 11

PR_LK11

Primary CPU's private lock for IPL 11

MAILBOX

Lock for sending messages to mailboxes

POOL

Lock on nonpaged pool database

PE RF MON

Lock for 1/0 performance monitoring

INVALIDATE

Lock for system space translation buffer (TB) invalidation

VI RT CONS

Lock for ownership of the virtual console

HWCLK

Lock on hardware clock database, including the quadword containing the due time of the
first timer queue entry (EXE$GQ_ 1ST_TIME) and the quadword containing the system time
(EXE$GQ_SYSTiiv'IEj

MEGA

Lock for serializing access to fork-wait queue

MCHECK

Lock for synchronizing certain machine error handling

EMB

Lock for allocating and releasing error logging buffers

For each spin lock, fork lock, or device lock in the sy~tem, SHOW
SPINLOCKS provides the following information:
•

Name of the spin lock (or device name ,.for the device lock)

•

Address of the spin lock data structure (SPL)

•

The owner CPU's CPU ID

•

IPL at which allocation of the lock is synchronized on a local processor

•

Number of nested acquisitions of the spin lock by the processor owning
the spin lock ("Ownership Depth")

•

Rank of the spin lock

•

Number of processors waiting to obtain the spin lock

•

Spin lock index

•

Timeout interval for spin lock acquisition (in terms of 10 milliseconds)

SHOW SPINLOCKS /BRIEF produces a condensed display of this same
information.
If the VAX system under analysis was executing with full-checking
multiprocessing enabled (according to the setting of the MULTIPROCESSING
system parameter), SHOW SPINLOCKS /FULL adds to the spin lock display
the last eight PCs at which the lock was acquired or released. If applicable,
SDA also displays the PC of the last release of multiple, nested acquisitions
of the lock.

SDA-152

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

EXAMPLES
iJ

SDA> SHOW SPINLOCKS
System static spinlock structures
EMB
Owner CPU ID
None
Ownership Depth
0000
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801B9EF8
1F
00
20

MC HECK
Owner CPU ID
None
Ownership Depth
0000
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801B9F48
1F
01
21

IOLOCK8
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
08
14
34

HAETAR$MBA
Owner CPU ID
None
Ownership Depth
0000
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA178
OB
08
37

HAETAR$NLA
Owner CPU ID
None
Ownership Depth
0000
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA178
08
08
37

HAETAR$PAA
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
14
14
37

System dynamic spinlock structures

----------------------------------

This excerpt illustrates the default output of the SHOW SPINLOCKS
command. Note that the fork lock IOLOCK8 is owned by the CPU whose
CPU ID is 2. CPU 2 must be executing at at least IPL 8, which is the
acquisition IPL of the fork lock. CPU 2 has no nested ownership of the fork
lock. The rank of IOLOCK8 is 14 16 , indicating that CPU 2 could not own any
locks with a logical rank of 15 16 or higher when it acquired IOLOCK8.

SDA-153

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

Similarly, while owning IOLOCK8, CPU 2 cannot obtain any additional spin
locks with a logical rank of 14 16 or below.
No CPUs are waiting for the fork lock; its index is 34 16 .

SDA> SHOW SPINLOCKS/BRIEF
IPL Rank Index Depth #Waiting
Address Spinlock Name

Owner CPU Interlock

---------------------------------------------------------------------------801B9EF8 EMB
801B9F48 MCHECK
801B9F98 MEGA
801B9FE8 HWCLK
801BA038 VIRTCONS
801BA088 INVALIDATE
801BAOD8 PERFMON
801BA128 POOL
801BA178 MAILBOX
801BA1C8 PR_LK11
801BA218 IOLOCK11
801BA268 PR_LK10
801BA2B8 IOLOCK10
801BA308 PR_LK9
801BA358 IOLOCK9
801BA3A8 SCHED
801BA3F8 MMG
801BA448 JIB
801BA498 TIMER
801BA4E8 PR_LK8
801BA538 IOLOCK8
801BA588 FILSYS
801BA5D8 QUEUEAST

1F
1F
1F
16
14
13
OF
OB
OB
OB
OB
OA
OA
09
09
08
08
08
08
08
08
08
06

Address

DIPL Rank Index Depth #Waiting

Device Name

00
01
02
03
04
05
06
07
08
09
OA
OB

oc
OD
OE
OF
10
11

12
13
14
15
16

20
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36

00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
01
00
00

0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000

None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
02
None
None

Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
Free
00
Free
Free

Owner CPU Interlock

---------------------------------------------------------------------------801BA178 HAETAR$MBA
801BA178 HAETAR$NLA
801BA538 HAETAR$PAA
8063C5CO HAETAR$XEA
8063C4AO HAETAR$XGA
8063C380 HAETAR$PEA
8063AC40 HAETAR$TXA
8063A520 HAETAR$LCA
801BA538 HAETAR$CNA

OB
08
14
15
15
14
15
15
08

08
08
14
FF
FF
FF
FF
FF
14

37
37
37
37
37
37
37
37
37

00
00
01
00
00
00
00
00
01

0000
0000
0000
0000
0000
0000
0000
0000
0000

None
None
02
None
None
None
None
None
02

Free
Free
00
Free
Free
Free
Free
Free
00

This excerpt illustrates the condensed form of the display produced in the
previous example.

SDA-154

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

SDA> SHOW SPINLOCKS/OWNED
System static spinlock structures
Address
IPL
Rank
Index

801BA538
08
14
34

HAETAR$PAA
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
14
14
34

HAETAR$CNA
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
08
14
34

HAETAR$NET
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
08
14
34

HAETAR$NDA
02
Owner CPU ID
Ownership Depth
0001
0000
CPUs Waiting
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
08
14
34

IOLOCK8
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

System dynamic spinlock structures

----------------------------------

The SHOW SPINLOCKS/OWNED command shows all owned spin locks in
the system.

SDA-155

SYSTEM DUMP ANALYZER
SHOW SPINLOCKS

SDA> SHOW SPINLOCKS/FULL
System static spinlock structures
EMB
Owner CPU ID
None
Ownership Depth
0000
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801B9EF8
1F
00
20

Spinlock EMB was last acquired or released from:
(Most recently)
80195146 ERL$WAKE+00089
801950EF ERL$WAKE+00032
80195146 ERL$WAKE+00089
801950EF ERL$WAKE+00032
80195146 ERL$WAKE+00089
801950EF ERL$WAKE+00032
80195146 ERL$WAKE+00089
(Least recently)
801950EF ERL$WAKE+00032

Last release of multiple acquisitions occurred at:
801194F9 EXE$INSIOQ+00044

IOLOCK8
Owner CPU ID
02
Ownership Depth
0001
CPUs Waiting
0000
Timeout interval 002DC60

Address
IPL
Rank
Index

801BA538
08
14
34

Spinlock IOLOCK8 was last acquired or released from:
801BBE08 EXE$FORKDSPTH+0007E
(Most recently)
80198EBF EXE$QIOACPPKT+00052
80198E7E EXE$QIOACPPKT+00011
80199BB2 IOC$CHECK_HWM+0032D
80182DE5 LCK$QUEUED_EXIT+0001D
80182884 LCK$AR_COMPAT_TBL+0007C
8018357E EXE$DEQ+00189
(Least recently)
80183428 EXE$DEQ+00033

The SHOW SPINLOCKS /FULL command displays a list of the last eight PCs
that have accessed the spin lock. For instance, the fork dispatcher contains
the code that most recently acquired the fork lock.

SDA-156

SYSTEM DUMP ANALYZER
SHOW STACK

SHOW STACK
Displays the location and contents of the four process stacks (of the SDA
current process) and the interrupt stack (of the SDA current CPU).

FORMAT

PARAMETERS

QUALIFIERS

SHOW STACK

range
]
[ /qualifier[, ... ]

range

Range of memory locations you want to display in stack format. You can
express a range using the following syntax:
m:n

Range of virtual addresses from m to n

m;n

Range of virtual addresses starting at m and continuing for n bytes

/ALL
Displays the locations and contents of the four process stacks for the current
SDA process and the interrupt stack for the SDA current CPU.

/EXECUTIVE
Shows the executive stack for the SDA current process.

/INTERRUPT
Shows the interrupt stack for the SDA current CPU.

/KERNEL
Shows the kernel stack for the SDA current process.

/SUPERVISOR
Shows the supervisor stack for the SDA current process.

/USER
Shows the user stack for the SDA current process.

DESCRIPTION

The SHOW STACK command, by default, displays the stack that was in use
when the system failed or, in the analysis of a running system, the current
operating stack. For any other process made the SDA current process, the
SHOW STACK command by default shows its current operating stack.
The various qualifiers to the command can display any of the four per-process
stacks for the SDA current process, as well as the interrupt stack for the SDA
current CPU.
You can define SDA process and CPU context by using the SET CPU, SHOW
CPU, SHOW CRASH, SET PROCESS, and SHOW PROCESS commands
as indicated in their command descriptions. A complete discussion of SDA
context control appears in Section 4.

SDA-157

SYSTEM DUMP ANALYZER
SHOW STACK

SDA provides the following information in each stack display:
Section

Contents

Identity of stack

SDA indicates whether the stack is a process stack
(user, supervisor, executive, or kernel) or the processor
interrupt stack. If the interrupt stack is being displayed,
SDA displays the CPU ID of the processor that owns it.
Similarly, if the SDA current process is currently scheduled
on a processor in the VAX system, SHOW ST ACK also
specifies the CPU ID of the processor on which the process
is scheduled.

Stack pointer

The stack pointer identifies the top of the stack. The
display indicates the stack pointer by the symbol SP => .

Stack address

SDA lists all the virtual addresses that the operating system
has allocated to the stack. The stack addresses are listed
in a column that increases in increments of 4 bytes (one
longword).

Stack contents

SDA lists the contents of the stack in a column to the right
of the stack addresses.

Symbols

SDA attempts to display the contents of a location
symbolically, using a symbol and an offset.
If the address is not within FFF 16 of the value of any
existing symbol, this column is left blank.

If a stack is empty, the display shows the following:
SP =>

(STACK IS EMPTY)

EXAMPLE
SDA> SHOW STACK
Process stacks (on CPU 00)
Current operating stack (USER) :
7FF73278
7FF7327C
7FF73280
7FF73284
SP =>

200COOOO
00001518
7FF732FO
000187A7

7FF73288 0000060A
7FF7328C 00000000
7FF73290 00000003
7FF73294 7FF73800
7FF73298 7FF73800

SGN$C_MAXPGFL+518
RMS$_ECH0+72E
BUG$_NOHDJMT+002

The SHOW STACK command displays a user stack which was the current
operating stack for a process scheduled on CPU 00. The data shown above
the stack pointer may not be valid. The symbol to the right of the columns,
BUG$_NOHDJMT+002, is the result of the SDA attempt to interpret the
contents of the longword at the top of the stack as a symbol meaningful
to the user. In this case the value on the stack and the value of BUG$_
NOHDJMT are unrelated.

SDA-158

SYSTEM DUMP ANALYZER
SHOW SUMMARY

SHOW SUMMARY
Displays a list of all active processes and the values of the parameters
used in swapping and scheduling these processes.

FORMAT

SHOW SUMMARY [/IMAGE]

PARAMETERS

None.

QUALIFIER

/IMAGE
Causes SDA to display, if possible, the name of the image being executed
within each process.

DESCRIPTION

The SHOW SUMMARY command displays the information in Table SDA-15
for each active process in the system.
Table SDA-15

Process Information in the SHOW SUMMARY
Display

Column

Contents

Extended PIO

32-bit number that uniquely identifies the process

lndx

Index of this process into the PCB array

Process name

Name assigned to the process

Username

Name of the user who created the process

State

Current state of the process, one of the following 14 states:

State

Meaning

COM

Computable and resident in memory

COMO

Computable, but outswapped

CUR

Currently executing 1

CEF

Waiting for a common event flag

LEF

Waiting for a local event flag

LEFO

Outswapped and waiting for a local event flag

HIB

Hibernating

HIBO

Hibernating and outswapped

SUSP

Suspended

1 For a process in the CUR state executing in a multiprocessing environment, SDA indicates
the CPU ID of the processor on which the process is current. This information, however,
may not be accurate in SHOW SUMMARY displays produced in the analysis of a running
system.

SDA-159

SYSTEM DUMP ANALYZER
SHOW SUMMARY

Table SDA-15 (Cont.)
Column

Process Information in the SHOW
SUMMARY Display

Contents
State

Meaning

SUSPO

Suspended and outswapped

PFW

Waiting for a page that is not in memory (page-fault
wait)

FPG

Waiting to add a page to its working set (free-page
wait)

COLPG

Waiting for a page collision to be resolved (collidedpage wait); this usually occurs when several
processes cause page faults on the same shared
page

MWAIT Waiting for a system resource (miscellaneous wait)
Pri

Current scheduling priority of the process

PCB

Address of the process control block

PHO

Address of the process header

Wkset

Number (in decimal) of pages currently in the process's
working set

EXAMPLE
SDA> SHOW SUMMARY/IMAGE
Current process summary
Extended Indx Process name
Username
State
Pri
PCB
PHD
Wkset
-- PID -- ---- --------------- ----------- -------------- -------33C00101 0001 SWAPPER
HIB
16 8000C3CO 8000C200
0
33C00205 0005 _RTA5:
SIVAD
LEF
4 80482FEO 82120EOO
293
33C00106 0006 ERRFMT
SYSTEM
HIB
8 80432950 80DB4600
126
$254$DUA200: [SYS6.SYSCOMMON.] [SYSEXE]ERRFMT.EXE;1
33C00107 0007 CACHE_SERVER
SYSTEM
HIB
16 80432ACO 81121EOO
120
$254$DUA200: [SYS6.SYSCOMMON.] [SYSEXE]FILESERV.EXE;400
33C00108 0008 CLUSTER_SERVER SYSTEM
HIB
10 804331FO 81246600
313
$254$DUA200: [SYS6.SYSCOMMON.] [SYSEXE]CSP.EXE;300

33C0010D OOOD NETACP
DECNET
CUR 00 10 8044C6DO 81608600
$254$DUA200: [SYS6.SYSCOMMON.]<SYSEXE>NETACP.EXE;3
33C0010E OOOE EVL
DECNET
HIB
4 8044CD60 817FCEOO
$254$DUA200: [SYS6.SYSCOMMON.]<SYSEXE>EVL.EXE

1500
68

The SHOW SUMMARY /INDEX command describes all active processes in
the VAX system at the time of the system failure. Note that the process
NETACP is in the CUR state on CPU 00 of a VAX multiprocessor at the time
of the failure.
SDA-160

SYSTEM DUMP ANALYZER
SHOW SYMBOL

SHOW SYMBOL
Displays the hexadecimal value of a symbol and, if the value is equal to an
address location, the contents of that location.

FORMAT
PARAMETER

SHOW SYMBOL [/ALL] symbol-name
symbol-name
Name of the symbol to be displayed. You must provide a symbol-name.

QUALIFIER

/ALL
Displays information on all symbols whose names begin with the characters
specified in symbol-name.

DESCRIPTION

The SHOW SYMBOL/ ALL command is useful for determining the names of
symbols that belong to a symbol set, as illustrated in the following example.

EXAMPLE
SDA> SHOW SYMBOL G
G = 80000000 : 8FBCOFFC

The SHOW SYMBOL command evaluates the symbol Gas 80000000 16 and
displays the contents of address 80000000 16 as 8FBCOFFC 16 .
SDA>

SHOW SYMBOL/ALL BUG

Symbols sorted by name

BUG$BUILD_HEADE 80002038 => 24A89F16
BUG$DUMP_REGIST 80002040 => 24A89F16
BUG$FATAL
80002048 => 24A89F16
BUG$L_BUGCHK_FL 80004108 => 00000001
BUG$L_FATAL_SPS 8000410C => 7FFE7C6C
BUG$READ_ERR_RE 80002050 => 24A89F16
BUG$REBOOT
80002058 => 6E9E9F17
BUG$TABLE
8000D09E => 00280001

BUG$_CONSOLRX50 00000640 => 10A2020E
BUG$_CONTRACT
OOOOOOCO
BUG$_CPUBUSYWAI 00000780 => 6501FB30
BUG$_CPUCEASED 000005E8 => 5EDDOOOO
BUG$_CPUEXIT
000006B8 => 218FD007
BUG$_CPUSANITY 00000778 => 8A031164
BUG$_CTERM
00000678 => 00000004
BUG$_CWSERR
00000698 => 004C414E

The preceding example shows the display produced by the SHOW
SYMBOL/ ALL command. SDA searches its symbol table for all symbols
that begin with the string "BUG" and displays the symbols and their values.
Although certain values equate to memory addresses, it is doubtful that the
contents of those addresses are actually relevant to the symbol definitions in
this instance.

SDA-161

SYSTEM DUMP ANALYZER
SPAWN

SPAWN
Creates a subprocess of the process currently running SDA, copying
the context of the current process to the subprocess and, optionally,
executing within the subprocess a specified command.

FORMAT
PARAMETER

SPAWN

{/qualifier{, .. .]] {command]

command
Name of the command that you want executed by the subprocess.

QUALIFIERS

/INPUT=filespec
Specifies an input file containing one or more command strings to be executed
by the spawned subprocess. If you specify a command string with an input
file, the command string is processed before the commands in the input file.
Once processing is complete, the subprocess is terminated.

/NOLOGICAL_NAMES
Specifies that the logical names of the parent process are not to be copied to
the subprocess. The default behavior is that the logical names of the parent
process are copied to the subprocess.

/NOSYMBOLS
Specifies that the DCL global and local symbols of the parent process are not
to be passed to the subprocess. The default behavior is that these symbols
are passed to the subprocess.

/NOTIFY
Specifies that a message is to be broadcast to SYS$0UTPUT when the
subprocess completes processing or aborts. The default behavior is that such
a message is not sent to SYS$0UTPUT.

/NO WAIT
Specifies that the system is not to wait until the subprocess is completed
before allowing more commands to be specified. This qualifier allows you
to specify new commands while the spawned subprocess is running. If
you specify /NOWAIT, you should use /OUTPUT to direct the output of
the subprocess to a file in order to prevent more than one process from
simultaneously using your terminal.
The default behavior is that the system waits until the subprocess is
completed before allowing more commands to be specified.

/OUTPUT=filespec
Specifies an output file to which the results of the SP AWN operation are
written. You should specify an output other than SYS$0UTPUT whenever
you specify /NOWAIT to prevent output from the spawned subprocess from
being displayed while you are specifying new commands. If you omit the
/OUTPUT qualifier, output is written to the current SYS$0UTPUT device.

SDA-162

SYSTEM DUMP ANALYZER
SPAWN

/PROCESS=process-name
Specifies the name of the subprocess to be created. The default name of the
subprocess is USERNAME_n, where USERNAME is the user name of the
parent process.

EXAMPLE
SDA> SPAWN
$ MAIL

DIR

LO
Process SYSTEM_1 logged out at 5-MAR-1989 15:42:23.59
SDA>
$

The previous example shows a general use of the SP AWN command to create
a subprocess that issues DCL commands to invoke the Mail Utility and list
the contents of a directory before logging off to return to the parent process
executing SDA.

SDA-163

SYSTEM DUMP ANALYZER
VALIDATE QUEUE

VALIDATE QUEUE
Validates the integrity of the specified queue by checking the pointers in
the queue.

FORMAT
PARAMETER

VALIDATE QUEUE

[address] [/SELF-RELATIVE]

address
Address of an element in a queue.
If you specify the period character (.) as the address, SDA uses the last

evaluated expression as the queue element's address.
If you do not specify an address, the VALIDATE QUEUE command
determines the address from the last issued VALIDATE QUEUE command in
the current SDA session.
If you do not specify an address, and no queue has previously been specified,
SDA displays the following error message:
%SDA-E-NOQUEUE, no queue has been specified for validation

QUALIFIER

/SELF_RELATIVE
Specifies that the selected queue is a self-relative queue.

DESCRIPTION

The VALIDATE QUEUE command uses the forward and backward pointers
in each element of the queue to make sure that all such pointers are valid and
that the integrity of the queue is intact. If the queue is intact, SDA displays
the following message:
Queue is complete, total of n elements in the queue

In these messages, n represents the number of entries the VALIDATE QUEUE
command has found in the queue.
If SDA discovers an error in the queue, it displays one of the following error
messages:
Error in forward queue linkage at address nnnnnnnn after tracing x elements
Error comparing backward link to previous structure address (nnnnnnnn)
Error occurred in queue element at address 00000000 after tracing pppp elements

These messages can appear frequently when the VALIDATE QUEUE
command is used within an SDA session that is analyzing a running system.
In a running system, the composition of a queue can change while the
command is tracing its links, thus producing an error message.
If there are no entries in the queue, SDA displays this message:
The queue is empty

SDA-164

SYSTEM DUMP ANALYZER
VALIDATE QUEUE

EXAMPLE
SDA> VALIDATE QUEUE/SELF_RELATIVE IOC$GL_IRPFL
Queue is complete, total of 159 elements in the queue

The previous example validates the self-relative queue that is the IRP
lookaside list. The validation is successful and determines that there are
159 IRPs in the list.

SDA-165

Index

Access violation• SDA-16, SDA-19
ACP (ancillary control process)• SDA-99
Addition operator ( +) • SDA-12
Address
examining• SDA-51
/ADDRESS qualifier• SDA-87, SDA-98,
SDA-123
/ALL qualifier• SDA-51, SDA-108, SDA-111,
SDA-115, SDA-126, SDA-143, SDA-157,
SDA-161
ANALYZE command• SDA-32
/CRASH_OUMP qualifier• SDA-35
/RELEASE qualifier• SDA-36
/SYMBOL qualifier• SDA-37
/SYSTEM qualifier• SDA-38
ANAL YZE/CRASH_OUMP command• SDA-6,
SDA-32
ANAL YZE/CRASH_OUMP /RELEASE command•
SDA-3
ANALYZE/SYSTEM command• SDA-2, SDA-32
Analyzing a crash dump

Backup Utility (BACKUP)
copying system dump file• SDA-4
Bad page list
displaying• SDA-115
/BAD qualifier• SDA-115
BOB (buffer descriptor block)• SDA-76
BOB summary page (BDBSUM) • SDA-76
Binary operator• SDA-12 to SDA-13
BLB (buffer lock block)• SDA-76
BMB summary page (BLBSUM) • SDA-76
Bugcheck
fatal conditions• SDA-16 to SDA-20
halt/restart• SDA-7
identifying• SDA-21
Bugcheck code• SDA-15
Bugcheck handling routines
global symbols• SDA-60
Bugcheck reason• SDA-94

See also Crash dump, System failure
privileges required• SDA-32
requirements• SDA-6
Analyzing a running system• SDA-38
See also System
privileges required• SDA-8, SDA-32
AND operator ( & ) • SDA-12
AP symbol• SDA-13
AOB (ACP queue block)• SDA-99
Argument pointer (AP)• SDA-13
Arithmetic operator• SDA-12
Arithmetic shifting operator (@) • SDA-13
ASB (asynchronous save block)• SDA-76
ASTL VL register
displaying• SDA-90
AST routines
global symbols• SDA-60
ATTACH command• SDA-41

c
Call frame
displaying in SDA • SDA-79
following a chain• SDA-79
Cancel 1/0 routine• SDA-99
CCB (channel control block)
displaying in SDA • SDA-76
CDDB (class driver data block)• SDA-99
CORP (class driver request packet)• SDA-87,
SDA-148
CDT (connection descriptor table)• SDA-87,
SDA-148
/CHANNEL qualifier• SDA-131
CLUB (cluster block)• SDA-83
CLUDCB (cluster quorum disk control block) •
SDA-83
CLUFCB (cluster failover control block)• SDA-83
Cluster management code
global symbols• SDA-60
CLUSTRLOA.STB • SDA-60
CLUSTRLOA symbol• SDA-13
Command• SDA-10 to SDA-14

lndex-1

Index

Condition handling routines
global symbols• SDA-60
Condition value
evaluating• SDA-48
examining• SDA-51
/CONDITION_ VALUE qualifier• SDA-48
Connection
displaying SDA information• SDA-87,
SDA-123, SDA-148
Connection manager
displaying SDA information• SDA-82
/CONNECTION qualifier• SDA-148
Context
SDA CPU• SDA-10
SDA process• SDA-9
Control block
formatting• SDA-56
Control region• SDA-14
base register• SDA-14
examining• SDA-52
length register• SDA-14
Control region operator (H) • SDA-12
Control region page table
displaying• SDA-127
COPY command• SDA-3, SDA-4, SDA-42
CPU context
changing• SDA-68, SDA-74, SDA-89,
SDA-93, SDA-126
displaying• SDA-89
CPU ID (CPU identification number)• SDA-89
CPULOA.EXE
global symbols• SDA-60
Crash dump
See also System failure
analysis• SDA-1 to ·soA-165
incomplete• SDA-7
short• SDA-7
Crash dump file
header• SDA-106
/CRASH_DUMP qualifier• SDA-6
CRB (channel request block)• SDA-99
CREATE command• SDA-2
CSB (cluster system block)• SDA-82, SDA-87
CSID (cluster system identification number)•
SDA-82, SDA-144
/CSID qualifier• SDA-82
Current location symbol ( . ) • SDA-13

lndex-2

D
Data structure
formatting• SDA-56
stepping through a linked list• SDA-64
Data structures
global symbols• SDA-60
DCLDEF.STB • SDA-60
DCL interpreter
global symbols• SDA-60
DOB (device data block)• SDA-99
DDT (driver dispatch table)• SDA-99
Decimal value of an expression• SDA-48
DECnet data structures
global symbols• SDA-60
DEFINE command• SDA-43
Device
displaying SDA information• SDA-98
Device driver
base address of driver prologue table (DPT)•
SDA-13
locating• SDA-13
locating a failing instruction• SDA-24
Device driver routine
address• SDA-99
Division operator ( /) • SDA-13
DPT (driver prologue table)• SDA-99
DPT base address• SDA-24
DUMP
subset• SDA-4
DUMPBUG parameter• SDA-2, SDA-28
Dump file
analyzing• SDA-32
copying the contents• SDA-42
DUMPSTYLE parameter• SDA-4

E
/ECHO qualifier• SDA-44
ERRORLOG.EXE • SDA-60
ERRORLOGBUFFERS parameter• SDA-3
Error logging routines
global symbols• SDA-60
ESP symbol• SDA-13
EVALUATE command• SDA-48
EV ALUA TE/PSL command• SDA-22
Event flag routines
global symbols• SDA-60

Index

EVENT_FLAGS_AND_ASTS. EXE
global symbols• SDA-60
EXAMINE command• SDA-16, SDA-24, SDA-51
EXAMINE/INSTRUCTION command• SDA-23
Exception
fatal• SDA-16
identifying causes of• SDA-21
EXCEPTION.EXE
global symbols• SDA-60
Exception handling routines
global symbols• SDA-60
Execute procedure• SDA-40
Executive image
contents• SDA-60, SDA-104
/EXECUTIVE qualifier• SDA-59, SDA-15 7
Executive stack pointer• SDA-13
EXIT command• SDA-55
Exiting from SDA • SDA-55
Expression• SDA-11 to SDA-14
evaluating• SDA-48

/GLOBAL qualifier• SDA-111
G operator• SDA-12
G symbol• SDA-14

H
Header
crash dump• SDA-106
/HEADER qualifier• SDA-118
HELP command• SDA-58
recording output• SDA-71
Hexadecimal value of an expression• SDA-48
H operator• SDA-12
H symbol• SDA-14

I
1/0 database

F
FAB (file attributes block)• SDA-76
Fatal exception• SDA-16
FAT ALEXCPT bugcheck • SDA-16
FCB (file control block)• SDA-76
Floating point emulation code
base address• SDA-13
FORMAT command• SDA-26, SDA-56, SDA-64
FPEMUL symbol• SDA-13
FP symbol• SDA-13
Frame pointer• SDA-13
Free page list
displaying• SDA-115
/FREE qualifier• SDA-115, SDA-118
FW A (file work area)• SDA-77

G
GBD (global buffer descriptor)• SDA-77
GBD (global buffer descriptor) summary page•
SDA-77
GBH (global buffer header)• SDA-77
GBSB (global buffer synchronization block) •
SDA-77
Global page table
displaying• SDA-111

displaying SDA information• SDA-98
global symbols• SDA-60
ICCS register
displaying• SDA-90
IDB (interrupt dispatch block)• SDA-99
IDX (index descriptor)• SDA-77
IFAB (internal file access block)• SDA-77
IFB (internal file access block)• SDA-77
IFI (internal file identifier)• SDA-76
/IF_ST A TE qualifier• SDA-44
Image activator
global symbols• SDA-60
Image 1/0 structures• SDA-77
/IMAGE qualifier• SDA-159
IMAGE_MANAGEMENT. EXE
global symbols• SDA-60
IMGDEF.STB• SDA-60
/INQEX qualifier•SDA-73, SDA-126
/INPUT qualifier• SDA-162
/INSTRUCTION qualifier• SDA-51
Interlocked queue
validating• SDA-164
/INTERRUPT qualifier• SDA-15 7
Interrupt stack
displaying contents• SDA-157
INVEXCEPTN bugcheck • SDA-16
IO_ROUTINES.EXE
global symbols• SDA-60

lndex-3

Index

IPL$_ASTDEL
PGFIPLHI bugcheck • SDA-19
IRAB (internal record access block)• SDA-77
IRB (internal record access block)• SDA-77
IRP (1/0 request packet)• SDA-99, SDA-118
IRP lookaside list
displaying contents• SDA-118
/IRP qualifier• SDA-118

J
JFB Oournaling file block)• SDA-77
JIB Oob information block)• SDA-128

K
/KERNEL qualifier• SDA-15 7
Kernel stack
displaying contents• SDA-15 7
Kernel stack pointer• SDA-14
Key
defining for SDA • SDA-43
/KEY qualifier• SDA-44
KSP symbol• SDA-14

L
Linker map
use in crash dump analysis• SDA-15
LKB (lock block)• SDA-108
LMF$GROUP_TABLE.EXE
global symbols• SDA-60
Location
examining• SDA-51
SDA default• SDA-51
translating to VAX MACRO instruction•
SDA-51
Lock
displaying SDA information• SDA-143
/LOCKID qualifier• SDA-143
LOCKING.EXE• SDA-60
Lock management routines
global symbols• SDA-60
Lock manager
displaying SDA information• SDA-108
Lock mode• SDA-144

lndex-4

/LOCKS qualifier• SDA-127
Logical AND operator ( & ) • SDA-12
Logical NOT operator ( #) • SDA-12
Logical operator• SDA-12
Logical OR operator ( I ) • SDA-12
Logical XOR operator ( \) • SDA-13
LOGICAL _NAMES.EXE
global symbols• SDA-60
Lookaside lists
displaying contents• SDA-118
LRP (large request packet)• SDA-118
LRP lookaside list
displaying• SDA-118
/LRP qualifier• SDA-118

M
MA 780 multi port memory
configuring a dump file for• SDA-3
Machine check code
base address• SDA-14
MCHK symbol• SDA-14
Mechanism array• SDA-17, SDA-22
Memory
examining• SDA-51
formatting• SDA-56
Memory location
decoding• SDA-53
examining• SDA-52
Memory region
examining• SDA-54
MESSAGE_ROUTINES. EXE
global symbols• SDA-61
MicroVAX 2000
inducing a crash• SDA-31
MicroVAX 3600 series
inducing a crash• SDA-31
MicroVAX I
inducing a crash• SDA-31
MicroVAX II
inducing a crash• SDA-31
Modified page list
displaying• SDA-115
/MODIFIED qualifier• SDA-115
Module
finding a failing• SDA-24
MSCP server code
base address• SDA-14
MSCP symbol• SDA-14

Index

Multiplication operator ( *) • SDA-12
Multiprocessing
global symbols• SDA-61
Multiprocessor
analyzing crash dumps• SDA-9
displaying synchronization structures•
SDA-150

N
NAM (name block)• SDA-77
Negative operator ( - ) • SDA-12
NET DEF .STB • SDA-60
nnDRIVER symbol• SDA-13
/NOLOGICAL_NAMES qualifier• SDA-162
Nonpaged dynamic storage pool
displaying contents• SDA-118
/NONPAGED qualifier• SDA-118
/NOSKIP qualifier• SDA-52
/NOSUPPRESS qualifier• SDA-52
/NOSYMBOLS qualifier• SDA-162
/NOTIFY qualifier• SDA-162
NOT operator ( #) • SDA-12
/NOW AIT qualifier •.SDA-162
NW A (network work area)• SDA-77

0
Operator• SDA-12
precedence of• SDA-12, SDA-13
OR operator (I)• SDA-12
/OUTPUT qualifier• SDA-162

p
POBR register
displaying• SDA-90
POBR symbol• SDA-14
POLR register
displaying• SDA-90
POLR symbol• SDA-14
PO page table
displaying• SDA-127
/PO qualifier•SDA-127
PO region
examining• SDA-52

P 1BR register
displaying• SDA-90
P1BR symbol•SDA-14
P 1LR register
displaying• SDA-90
P1LR symbol•SDA-14
P 1 page table
displaying• SDA-127
/P 1 qualifier• SDA-52, SDA-127
P1 region
examining• SDA-52
Paged dynamic storage pool
displaying contents• SDA-118
/PAGED qualifier• SDA-118
Page fault
illegal• SDA-19
Page table
displaying• SDA-111, SDA-127
Page table entry
evaluating• SDA-48
examining• SDA-52
PAGE_MANAGEMENT .EXE
global symbols• SDA-61
/PAGE_TABLES qualifier• SDA-127
Paging file
See also SYS$SYSTEM:PAGEFILE.SYS
as system dump file• SDA-5
Parenthesis
as precedence operator• SDA-13
/PARENT qualifier• SDA-4 1
PB (path block)• SDA-99
PCB (process control block)• SDA-160
displaying• SDA-127
hardware• SDA-129
PCBB register
displaying• SDA-90
/PCB qualifier• SDA-127
PC symbol• SDA-14
PDT (port descriptor table)• SDA-123
PFN (page frame number) database• SDA-111
displaying• SDA-115
PGFIPLHI bugcheck • SDA-19
PHO (process header)• SDA-160
displaying• SDA-127
/PHO qualifier•SDA-127
Port
displaying SDA information• SDA-123
Port driver
displaying SDA information• SDA-82
Positive operator ( +) • SDA-12
Precedence of operators• SDA-12

lndex-5

Index

Precedence operator• SDA-13
PRIMITIVE_IQ.EXE
global symbols• SDA-61
Process
channel• SDA-126
displaying SDA information• SDA-126,
SDA-159
examining a hung• SDA-8
image• SDA-159
listening• SDA-83
lock• SDA-127
scheduling state•SDA-129, SDA-159
spawning a subprocess• SDA-162
Process context
changing• SDA-68, SDA-73, SDA-93,
SDA-126
Process control region• SDA-14
Process control region operator (H) • SDA-12
Process identification• SDA-126
Process index• SDA-126
Process name• SDA-126
Processor context
changing• SDA-68, SDA-74, SDA-89,
SDA-93, SDA-126
Processor-specific loadable code
base address•SDA-14
Processor status longword
See PSL
Processor type
displaying• SDA-90
Process-permanent 1/0 structures• SDA-77
/PROCESS qualifier• SDA-163
PROCESS_MANAGEMENT. EXE
global symbols• SDA-61
/PROCESS_SECTION_TABLE qualifier• SDA-127
Program counter• SDA-14
Program counter (PC)
in a crash dump• SDA-15
Program region
base register• SDA-14
examining• SDA-52
length register• SDA-14
Program region page table
displaying• SDA-127
PSL•SDA-14
PSL (processor status longword)
evaluating• SDA-22, SDA-48
examining• SDA-52
/PSL qualifier• SDA-52
PSL symbol•SDA-14

lndex-6

PST (process section table)
displaying• SDA-127
/PTE qualifier• SDA-48, SDA-52

Q
Queue
stepping through• SDA-64
validating• SDA-164
Quorum• SDA-82

R
RAB (record attributes block)• SDA-77
Radix
default• SDA-12
Radix operator• SDA-12
RDT (response descriptor table)• SDA-148
READ command• SDA-59
SYS$DISK • SDA-60
READ /EXECUTIVE command• SDA-16
Recovery unit system services
global symbols• SDA-61
RECOVERY_UNIT_SERVICES. EXE
global symbols• SDA-61
Register
displaying• SDA-89, SDA-127
general• SDA-14
/REGISTERS qualifier• SDA-127
/RELEASE qualifier• SDA-3
/RELOCATE qualifier• SDA-59
REPEAT command• SDA-64
Report system event
global symbols• SDA-61
Resource
displaying SDA information• SDA-143
RLB (record lock block)• SDA-77
RMS.EXE• SDA-61
RMSDEF .STB • SDA-60
RMS image
base address• SDA-14
/RMS qualifier• SDA-127
RMS symbol• SDA-14
RSB (resource block)• SDA-109, SDA-143
RSPID (response ID)
displaying SDA information• SDA-148
RUB (recovery unit block)• SDA-77

Index

RUFB (recovery unit file block)• SDA-77
RUSB (recovery unit stream block)• SDA-77

s
SO region
examining• SDA-52
SAVEDUMP parameter• SDA-3, SDA-28
SB (system block)• SDA-83, SDA-99
SBR register
displaying• SDA-90
SCBB register
displaying• SDA-90
Scheduler
global symbols• SDA-61
SCS (system communications services)
base address• SDA-14
displaying SDA information• SDA-82
SDA-83, SDA-87, SDA-123, SDA-148
global symbols• SDA-60
SCSDEF .STB • SDA-60
SCSLOA symbol• SDA-14
/SCS qualifier• SDA-82
SDA$1NIT logical name• SDA-8
SDA current CPU•SDA-10, SDA-68, SDA-74,
SDA-89,SDA-93,SDA-126,SDA-157
SDA current process• SDA-9, SDA-10, SDA-68,
SDA-73,SDA-93,SDA-126,SDA-157
SDA symbol table• SDA-13
building• SDA-7
expanding• SDA-8
SEARCH command• SDA-66
SECURITY.EXE
global symbols• SDA-61
Self relative queue
validating• SDA-164
/SELF_RELATIVE qualifier• SDA-164
SET CPU command• SDA-10, SDA-68
analyzing a running system• SDA-9
SET LOG command• SDA-71
compared with SET OUTPUT command•
SDA-71
SET NOLOG command• SDA-71
SET OUTPUT command• SDA-7 2
compared with SET LOG command• SDA-71
SET PROCESS command• SDA-9, SDA-73
SET RMS command• SDA-76
/SET_ST A TE qualifier• SDA-45
SFSB (shared file synchronization block)• SDA-77

Shadow set
displaying SDA information• SDA-99
Shifting operator (@) • SDA-13
SHOW CALL_FRAME command• SDA-65,
SDA-79
SHOW CLUSTER command• SDA-82
SHOW CLUSTER/SCS command• SDA-123
SHOW CONNECTIONS command• SDA-87
SHOW CPU command• SDA-10, SDA-68,
SDA-89
analyzing a running system• SDA-9
SHOW CRASH command• SDA-10, SDA-15,
SDA-16,SDA-68,SDA-93
analyzing a running system• SDA-9
SHOW DEVICE command• SDA-15, SDA-24,
SDA-98
SHOW EXECUTIVE command• SDA-15,
SDA-104
SHOW HEADER command• SDA-106
SHOW LOCK command• SDA-108
SHOW MEMORY command• SDA-3
SHOW PAGE_TABLE command• SDA-23,
SDA-111
SHOW PFN_DATA command• SDA-115
SHOW POOL command• SDA-118
SHOW PORTS command• SDA-123
SHOW PROCESS/ ALL command• SDA-128
SHOW PROCESS command•SDA-74, SDA-126
SHOW PROCESS/LOCKS command• SDA-108
SHOW PROCESS/RMS command• SDA-14 7
selecting display options• SDA-76
SHOW RESOURCE command• SDA-108,
SDA-143
SHOW RMS command• SDA-14 7
SHOW RSPID command• SDA-148
SHOW SPINLOCKS command• SDA-151
SHOW ST ACK command• SDA-21, SDA-157
SHOW SUMMARY command•SDA-126,
SDA-159
SHOW SYMBOL command• SDA-161
Shutdown
operator-requested• SDA-5
SID register
displaying• SDA-90
Signal array• SDA-18
SISR register
displaying• SDA-90
Site-specific startup procedure
See SYS$MANAGER:SYSTARTUP.COM
SLR register
displaying• SDA-90
SPAWN command• SDA-162

lndex-7

Index

Spin lock
displaying SDA information• SDA-150
owned• SDA-90
SPR (Software Performance Report)• SDA-2,
SDA-28
SP symbol• SDA-14
SRP (small request packet)• SDA-119
SRP lookaside list
displaying contents• SDA-119
/SRP qualifier• SDA-119
SSP symbol• SDA-14
SSRVEXCEPT bugcheck • SDA-16
Stack
displaying contents• SDA-15 7
Stack frame
displaying in SDA • SDA-79
following a chain• SDA-79
Stack pointer
Start 1/0 routine• SDA-99
Subprocess• SDA-162
Subtraction operator ( - ) • SDA-12
/SUMMARY qualifier• SDA-119
/SUPERVISOR qualifier• SDA-15 7
Supervisor stack
displaying contents• SDA-15 7
Supervisor stack pointer• SDA-14
Swapper
global symbols• SDA-61
Symbol• SDA-13 to SDA-14, SDA-23
defining for SDA • SDA-43
displaying• SDA-14
evaluating• SDA-161
listing• SDA-161
loading into the SDA symbol table• SDA-59
name•SDA-13,SDA-43
representing executive modules• SDA-104
user-defined• SDA-43
/SYMBOLS qualifier for EVALUATE• SDA-48
Symbol table
See also SDA symbol table, System symbol
table
specifying an alternate SDA • SDA-37
Symbol table file
reading into SDA symbol table• SDA-59
SYS$DISK as SDA output• SDA-72
SYS$DISK global read• SDA-60
SYS$MANAGER:SYST ARTUP .COM
invoking SDA • SDA-5
producing an SDA listing• SDA-5
releasing page file blocks• SDA-3

lndex-8

SYS$SYSTEM :OPCCRASH. COM
involvement in writing crash dump• SDA-5
SYS$SYSTEM:PAGEFILE.SYS • SDA-5, SDA-28
See also System dump file
as dump file• SDA-3
releasing blocks containing a crash dump•
SDA-36
SYS$SYSTEM:REOSYSDEF.STB • SDA-6,
SDA-7
SYS$SYSTEM :SHUTDOWN .COM
involvement in writing crash dump• SDA-5
SYS$SYSTEM:SYS.EXE • SDA-59
contents• SDA-60, SDA-104
SYS$SYSTEM:SYS.STB•SDA-6, SDA-7,
SDA-9, SDA-15
SYS$SYSTEM:SYSDEF.STB • SDA-8
SYS$SYSTEM:SYSDUMP.DMP • SDA-28
See also System dump file
protection• SDA-5
size of• SDA-3
SYSAP (system application)• SDA-148
SYSDEVICE. EXE
global symbols• SDA-61
SYSGETSYI. EXE
global symbols• SDA-61
SYSLICENSE. EXE
global symbols• SDA-61
SYSLOA symbol• SDA-14
SYSMSG.EXE
global symbols• SDA-61
System
analyzing a running• SDA-2, SDA-8 to SDA-9,
SDA-32
investigating performance problems• SDA-8
System dump file• SDA-2 to SDA-3
copying• SDA-4
header• SDA-5
mapping physical memory to• SDA-7
requirements for analysis• SDA-6
saving• SDA-4
size•SDA-3
System failure
analyzing• SDA-15 to SDA-28
causing• SDA-28 to SDA-31
diagnosing from PC contents• SDA-15
example• SDA-21 to SDA-28
summary• SDA-93
System hang• SDA-28
System image
contents• SDA-60, SDA-104

Index

System management
creating a crash dump file• SDA-2
System map• SDA-15
System message routines
global symbols• SDA-61
System page table (SPT)
displaying• SDA-23, SDA-111
in system dump file• SDA-2, SDA-7
System paging file
as dump file• SDA-3
releasing blocks containing a crash dump•
SDA-36
System PCB (process control block)
displaying• SDA-128
System process• SDA-73
/SYSTEM qualifier• SDA-52, SDA-73,
SDA-111, SDA-115, SDA-128
System region
examining• SDA-52
System space
base address• SDA-14
System space operator (G) • SDA-12
System symbol table• SDA-6, SDA-13
System time quadword
examining• SDA-52
SYSTEM _PRIMITIVES. EXE
global symbols• SDA-61
SYSTEM _SYNCHRONIZATION. EXE
global symbols• SDA-61

T
Terminal key
defining for SDA • SDA-43
/TERMINATE qualifier• SDA-45
/TIME qualifier• SDA-52
/TYPE qualifier• SDA-56, SDA-119

u
UCB (unit control block)• SDA-87
Unary operator• SDA-12
/USER qualifier• SDA-157
User stack
displaying contents• SDA-15 7
User stack pointer• SDA-14
USP symbol• SDA-14

v
VALIDA TE QUEUE command• SDA-164
VAX-11/725
inducing a crash• SDA-31
VAX-11/730
inducing a crash• SDA-31
VAX-11/750
inducing a crash• SDA-31
VAX-11/780
inducing a crash• SDA-30
VAX-11 /785
inducing a crash• SDA-30
VAX 6200 series
inducing a crash• SDA-29
VAX 8200
inducing a crash• SDA-29
VAX 8230
inducing a crash• SDA-29
VAX 8250
inducing a crash• SDA-29
VAX 8300
inducing a crash• SDA-29
VAX 8350
inducing a crash• SDA-29
VAX 8530
inducing a crash• SDA-29
VAX 8550
inducing a crash• SDA-29
VAX 8600
inducing a crash• SDA-30
VAX 8650
inducing a crash• SDA-30
VAX 8700
inducing a crash• SDA-29
VAX 8800
inducing a crash• SDA-29
VAX 8830
inducing a crash• SDA-29
VAX 8850
inducing a crash• SDA-29
VAXcluster
base address of loadable code• SDA-13
displaying SDA information• SDA-82
VAX MACRO instruction
formatting memory with SDA • SDA-51
V AXstation II
inducing a crash• SDA-31
VCB (volume control block)• SDA-99
Virtual address operator (@) • SDA-12

lndex-9

Index

Virtual address space
sufficient for system dump analysis• SDA-6
VIRTUALPAGECNT parameter• SDA-6
VMS executive image
global symbols• SDA-59
VMS Record Management Services (RMS)
data structures shown by SDA • SDA-76
displaying data structures• SDA-12 7,
SDA-147
global symbols• SDA-60, SDA-61
VMS system image
global symbols• SDA-59
Vote•.SDA-82

w
WCB (window control block)• SDA-77
Working set list
displaying• SDA-128
/WORKING_SET qualifier• SDA-128
WORKING_SET_MANAGEMENT.EXE
global symbols• SDA-61

x
XAB (extended attribute block)• SDA-77
XOR operator (\) • SDA-13
XOP (extended 010 processor)• SDA-99

lndex-10

Reader's Comments

VMS System Dump
Analyzer Utility Manual
AA-LA87 A-TE

Please use this postage-paid form to comment on this manual. If you require a written reply to a software
problem and are eligible to receive one under Software Performance Report (SPR) service, submit your
comments on an SPR form.
Thank you for your assistance.

I rate this manual's:
Accuracy (software works as manual says)
Completeness (enough information)
Clarity (easy to understand)
Organization (structure of subject matter)
Figures (useful)
Examples (useful)
Index (ability to find topic)
Page layout (easy to find information)

Excellent

Good

Fair

Poor

D
D
D
D
D
D
D
D

D
D
D
D
D.
D
D
D

I would like to see more /less

What I like best about this manual is

What I like least about this manual is

I found the following errors in this manual:
Page

Description

Additional comments or suggestions to improve this manual:

I am using Version ___ of the software this manual describes.

Name/Title

Dept.

Company

Date

Mailing Address
Phone

-- ~o;~;;~:·d Here ~d Tape ------------------~lllf-------;~ ~y~---

in the
United States

BUSINESS REPLY MAIL
FIRST CLASS PERMIT NO. 33 MAYNARD MASS.
POST AGE WILL BE PAID BY ADDRESSEE

DIGIT AL EQUIPMENT CORPORATION
Corporate User Publications-Spit Brook
ZK01-3/J35 110 SPIT BROOK ROAD
NASHUA, NH 03062-9987

111 ..... 11.11 .... 11 .... 1.11.1 .. 1.1 .. 1•• 1.1 ••• 1.11 .. 1
- - Do Not Tear - Fold Here - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -