Contents
Part 1. Control Program (CP) ...•....•...•....•••..••..••...••..••..••...•••...••... 1 VM/SP .•...•........•...•....•••..••......••...•••.....•.....•................. 2
Introduction to the VM/SP Control Program ............................................ 2
Virtual Machine Time Management ................................................ 3
Virtual Machine Storage Management .............................................. 3
Virtual Storage Preservation ...................................................... 7
Virtual Machine I/O Management ................................................. 9
Spooling Functions ............................................................ 11 Spool File Recovery ............................................................ 12
CP Commands ............................................................... 13
Program States •...•...•.....••.......•...••...•••.••..•••.••..••••...••...••..•• 14 Using Processor Resources ....•••.....• ',' •••.•••..••.•••.••..•.••••••...••...•.....• 15
Queue 1 ....................................................................... 15
Queue 2 ....................................................................... 15
Deadline Priority ..... '............................................................ 16
Queue 3 ....................................................................... 17
Interruption Handling •• "............................................................. 18
I/O Interrupts ................................................................... 18
Missing Interrupt Handler .......................................................... 18 Using the Missing Interrupt Handler ............................................... 18
Devices Monitored ............................................................ 19
Default Time Interval Values ..................................................... 19
Changing the Time Interval ...................................................... 20 Determining Time Interval Settings ................................................ 21
Diagnostic Aids ............................................................... 21 System Messages .............................................................. 21
System's Error Recording Area ................................................... 22
Trace Table .................................................................. 22
Program Interrupt ................................................................ 22
Machine Check Interrupt .......................................................... 22 SVC Interrupt ................................................................... 23
External Interrupt ................................................................ 23
Synchronous Interrupts in an Attached Processor or Multiprocessor System ................... 23
Real I/O Interrupts ............................................................... 23
Performance Guidelines ••..•••.••••.•.••..•.....•••..••••••••.••••.••••.•.•••••.••• 24
General Information .............................................................. 24
Virtual Machine I/O .............................................................. 25
Paging Considerations ............................................................ 26
Locked Pages Option ........................................................... 27
Reserved Page Frames Option .................................................... 28
Virtual=RealOption ........................................................... 28 VM/SP Performance Options ....................................................... 29
Favored Execution ............................................................ 30 User Priority ................................................................. 31
Reserved Page Frames .......................................................... 32
Virtual=Real ................................................................. 32
Affinity ..................................................................... 34
Multiple Shadow Table Support .................................................. 35 Shadow Table Bypass .......................................................... 35
Queue Drop Elimination ........................................................ 36
Virtual Machine Assist Feature ................................................... 37 Using the Virtual Machine Assist Feature ........................................... 38
Restricted Use of the Virtual Machine Assist Feature .................................. 38
Extended Control-Program Support:VM/370 (ECPS) .................................... 39 Using the Extended Control-Program Support: VM/370 .............................. 41
Channel Usage .................................................................. 41
The Virtual Block Multiplexer Channel Option ....................................... 41
Multisystem Communications .................................................... 42
Alternate Path Support ......................................................... 44 MVS/System Extensions Support .................................................... 45
Contents xv

Low Address Protection Facility .................................................. 46
Common Segment Facility ....................................................... 46
Special MVS Instruction Operation Handling Facilities ............................... ,. 46
Enabling MVS/System Extensions Support ......................................... 47
Single Processor Mode ......................................................... 47
Dynamic System Control Programming (SCP) Transition to or from Native Mode ........... 47
Performance Observation and Analysis •••••••..•••••••••••••••••••••••••••••••••••••.•• 49
Load Indicators .................................................................. 49
The INDICATE Command ......................................................... 49
The INDICATE FAVORED Command ............................................ 50 Managing Page Migration ....................................................... 50 Querying and Setting the System Resource Management Variables .......................... 51
Querying and Setting the Paging Variable ........................................... 51
The MONITOR Command ......................................................... 52
Implemented Classes ........................................................... 54 VM/SP Monitor Response to Unusual Tape Conditions ................................ 56 VM/SP Monitor Considerations .................................................. 56 VM/SP Monitor Data Volume and Overhead ........................................ 58
Load Environments of VM/SP ................................................... 59
Trace Table Recording Facility ...................................................... 61
Accounting Records ••.•••••••.•••••••••••••••••••••••••••••••••.•••••••••••.••••••• 69
Accounting Records for Virtual Machine Resource Usage ................................. 69
Accounting Records for Dedicated Devices and Temporary Disk Space ....................... 69
Accounting Records for LOGON, AUTOLOG, and LINK Journaling ...................... " .. 70 Accounting Records Created by the User .............................................. 71 User Accounting Options .......................................................... 72
Generating Saved Systems ••••••••..••.••••••••••••••••••••••••••••••••••••••••••••• 73
The NAMESYS Macro for Saved Systems ............................................. 73
Coding the NAMESYS Macro ................................................... 73
Example of a DMKSNT Entry ................................................... 73 Using the SA VESYS Command ..................................................... 74
Shared Segments ................................................................. 75
Special Considerations for Shared Segments ......................................... 75
Discontiguous Saved Segments ...................................................... 75 User Requirements ............................................................ 76
Loading and Saving Discontiguous Shared Segments ................................... 77
How the Interface Works ....................................................... 78
Shared Segment Protection ......................................................... 79
Virtual Machine Operation ...................................................... 80 The NAMENCP Macro for 370X Control Program .... '" .................. , ............ 81
Coding the NAMENCP Macro ................................................... 81
Example of a NAMENCP Entry .................................................. 81 Using the SA VENCP Command .................................................... 81
The Virtual Machine Communication Facility •••••••••.•••••••••••••••••••••••••••••.•••• 83 Using the Virtual Machine Communication Facility ...................................... 84
VMCF Applications ........................................................... 85
Security and Data Integrity ...................................................... 86
Performance Considerations ..................................................... 86
General Considerations ......................................................... 87
VMCF Protocol ............................................ . . . . . . . . . . . . . . . . . . . . . . 87
The SEND Protocol ............................................................ 88
The SEND/RECV Protocol ..................................................... 89
The SENDX Protocol .......................................................... 90 The IDENTIFY Protocol ..................................................... , .. 91
Descriptions of VMCF Subfunctions ................................................. 91
The Control Subfunctions ....................................................... 91
The Data Transfer Functions .................................................... 94
Invoking VMCF Subfunctions ...................................................... 97
Diagnose Code X'68' .......................................................... 98
The VMCP ARM Parameter List .................................................. 98
External Interrupt Code X'4001' ................................................ 103 VMCF User Doubleword ...................................................... 106 DIAGNOSE X'68' Return Codes ................................................ 106
Data Transfer Error Codes ..................................................... 109 xvi VM/SP System Programmer's Guide