April 1, 1981
vi IBM VM/370 System programmer's Guide

Page of GC20-1807-7 As Updated April 1, 1981 by TNL GN25-0829
Contents
The entries in this Table of Contents are accumulative. They list additions to this
publication by the following VM/370 System Control Proqram Products: • VM/370 Basic System Extensions, program Number 5748-XX8 • VM/370 System Extensions, program Nu mber 5748-XEl However, the text within the publication is not accumulative; it only relates to the one SCP program product that is installed on your system. Therefore, there may be topics ana references listed in this Tarle of contents that are not contained in the body of this P ubI ica tion.
Summary of Amendments. xiii PART 1. DEBUGGING WITH VM/370. • • 1 INTRODUCTION TO DEEUGGING.. • .3
How To Start Debugging • • • • .3
Does a Problem Exist? •• 4 Identifying the Problem. • ••••• 7
Analyzing the Problem. • • 13
How To Use VM/370 Facilities To Debug •• 18
Abend. • • • • • • • • 18 CP Abend • • • • • • • • • 18 CMS Abend. • • • • • • • • 19 Virtual Machine Abend (other than CM S). • • • • • • Un exp ect ed Results • • • • • • Unexpected Results in CP • • Unexpected Results in a Virtual • 23 • 24 • 24 Machine • • • • • 24 Loop • • • • • • • • • 25 CP Disabled Loop •• • • • • 25
wait • • • • • • • • 27
Summary of VM/370 Debugging • 32
Comparison of CP and CMS Facilities for
Debugging • • • • • • • • • • • • • • • 37
An Overview of VM/370 Commands That Can
Be Used for Debugging • • • • • • • 38
Commands that Display or Dump
virt ual Machine Data. • • • • • • 38
Commands That Set and Query System
Features, Conditions, and EVents ••• 39
Commands To Collect and Analyze System
Information • • • • • • • • • • • • • 40 Commands That Trace EVents in Virtual Machines •••••••••••• Commands That Alter the Contents of
storage • • . • • • • • • • • • Debugging CP on a Virtual Machine. CP Internal Trace Table. • • • Abend Dumps •••••••••• • 40 • 41 • 42 • 42 • 44
How To Print a CP Abend Dump From Tape 45 Reading CP ABEN D Dumps
Reason for tbe Abend
Collect Information •• Register Usage • • • • • ••• • 46 • 46 • 47 • 48 Save Area Conventions. • Virtual and Real Control
Identifying and Locating • 48 Elock Status. 50 a pageable
Module. • • • • ••••••••••• 63 VMDUMP Records: Format and Content 63
Locating Logical Dump Records. • 64 DEBUGGING WITH CMS • • CMS Debugging Commands • DEBUG. • • •• • • • • 64.2 •• 64.2 • 65
Nucleus Load Map ••••• Load Map • • • • • • • Reading CMS Abend Dumps •• • • • • • 66
Reason for the Abend
Collect Inf ormation.
Register Usage ••• PART 2. CONTROL PROGRAM (CP) VM/370 •••••••••••••• Introduction to the VM/370 Control • 68 • 68 • 69 • 70 • 72 • 73 • 75
Program • • • • • • • • • • • •• • 75 Virtual Machine Time Management. .' 76 Virtual Machine Storage Management • • 76 Virtual Storage Preservation ••••••••••••• 78.1 Virtual Storage Preservation (.2148-1 E i). • • • • • • • • • Virtual Machine I/O Management • Spooling Functions • • 78.1 • 79 • 80 Spool File Recovery. • 81 CP Commands. • 82 PROGRAM STATES • • 83 USING PROCESSOR RESOURCES. 84 Queue 1 •••••••••••••• Queue 2. • • • • • • • • • • • • • • 84 • 84 Deadline Priority Deadline Priority Queue 3 • • • • Queue 3 (5748-XE1) INTERRUPTION HANDLING •• INTERRUPTION HANDLING (5748-XX8) INTERRUPTION HANDLING I/O Interrupts • • • • • • • I/O InterrUpts (.2148-XX.m"-. • • • 85 • 85 • 86 • 86 • 8E 86.1 • • • 86.1 • 86 • •• 86.1 • •• 86.1 · 86 • • • • • 86.1 I/O Interrupts (5748-XEj) •• Program Interrupt. • • • • • Program Interrupt (5748-XX8) Program Interrupt Machine Check Interrupt. • • • 86.1 • 86
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