RSSBK Back to Index page
 
Prolog 
Control Block Contents 
   RSSBK DSECT
Storage Layout 
Cross Reference (Contains links to field and bit definitions)
Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM.


  RSSBK Prolog Top of page
 
 NAME       : HCPRSSBK
 DESCRIPTION: RECORDING SYSTEM SERVICE BLOCK
 DSECT      : RSSBK
 FUNCTION   : MAPS OUT THE HEADER OF SYSTEM RECORDS ON THE
              RECORDING QUEUE.
 LOCATED BY : RTHQUE
              RSSNEXT CHAINED
 DELETED BY : HCPREC
 RELOCATION CONSIDERATIONS : None
 COMPATIBILITY AND MIGRATION CONCERNS : This control block gets checkpointed during SHUTDOWN and
              will be read back in during a WARM start.  Therefore, if
              the format of the block changes due to service being
              applied before the warm start, code should be in place to
              distinguish between the old and new format.  (See the
              note below describing the RSSVERS field.)
 
 
  RSSBK Control Block Content Top of page
 

 RSSBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure RSSBK RECORDING SYSTEM SERVICE BLOCK 0000 0 Address 4 RSSNEXT Pointer to next RSSBK 0004 4 Signed 2 RSSUSCNT SYSTEM RECORD USE COUNT 0006 6 Signed 2 RSSVN00M (0) PLACE HOLDER (VERSION 00 INFO) 0006 6 Signed 2 * RESERVED 0008 8 Bitstring 1 * RESERVED 0009 9 Bitstring 1 RSSRID SYSTEM RECORD ID 00000001 RSSRACNT X'01' RSSRACNT Accounting record 00000002 RSSRIOER X'02' RSSRIOER EREP (LOGREC) record 00000003 RSSRSYMP X'03' RSSRSYMP Sympton record 00000004 RSSRCNFG X'04' RSSRCNFG Configuration record 000000FF RSSRTAB X'FF' RSSRTAB Recording table (if set block mapped by the RTHBK not the RSSBK, RSSRID must remain at the same offset as RTHRID) 000A 10 Signed 2 RSSFRESZ RSSBK BLOCK SIZE IN DOUBLE WORDS 000C 12 Bitstring 1 RSSFLAG FLAGS DEFINED FOR RECORDING SYSTEM SERVICES 1... .... RSSRINIT X'80' RSSRINIT RECORD INITIALIZED TO RECORDING TABLE .1.. .... RSSRINC X'40' RSSRINC RECORD INCOMPLETE ..1. .... RSSNOMON X'20' RSSNOMON Record not monitored by Free Storage Limit Detection function NOTES : The following field is used to indicate when the RSSBK format has changed and what that change was due to. Any code defined here should be checked in HCPRECKP when old format RSSBKs are read from the checkpoint cylinders. The old format RSSBKs should then be updated appropriately to the new format. Code should also be added to HCPRIUCF and HCPRECRI to set the code for any RSSBKs that are being newly created AFTER the format change. A new code should only need to be defined here when a change to the RSSBK causes it to be incompatible with a previous format (as in the case of the RSSMSGN field being expanded from a halfword to a fullword). Due to compatibility, the displacement of RSSVERS should NEVER change. Previous versions of this control block had this field marked 'RESERVED' and the field was known to be zero. Therefore, previous versions were version X'00'. In addition, RSSFLAG should never be moved. This field is used without regard to the version of the RSSBK. 000D 13 Bitstring 1 RSSVERS RSSBK VERSION INDICATOR 00000000 RSSVN00 X'00' RSSVN00 For version 00, original format 00000001 RSSVN01 X'01' RSSVN01 For version 01, the RSSMSGN field was expanded from a halfword to fullword 000E 14 Signed 2 RSSDCNT LENGTH OF RSSDATA IN BYTES 0010 16 Signed 4 RSSMSGN SYSTEM RECORD MESSAGE NUMBER 0014 20 Signed 4 * RESERVED 0018 24 Character 1 RSSDATA (0) START OF VARIABLE LENGTH SYSTEM RECORD DATA 00000018 RSSBLEN *-RSSBK RSSBK HEADER LENGTH IN BYTES 00000003 RSSSIZE (*-RSSBK+7)/8 RSSBK ENTRY IN DOUBLEWORDS The following mapping shows what the fields changed for the Version 01 RSSBK looked like in Version 00. The following fields are used when updating Version 00 RSSBKs to Version 01. 0006 6 Signed 2 RSSV00MN RSSMSGN FIELD (Version 00 Format) 0010 16 Character 1 RSSV00DA (0) RSSDATA FIELD (Version 00 Format) 00000010 RSSV00HL *-RSSBK Length of a Version 00 Header
 
 
  RSSBK Storage Layout Top of page
 
          
*** RSSBK - RECORDING SYSTEM SERVICE BLOCK
*
*     +---------------------------+-------------+-------------+
*   0 |         RSSNEXT           |  RSSUSCNT   |/////////////|
*     +------+------+-------------+------+------+-------------+
*   8 |//////|RSSRID|  RSSFRESZ   |:FLAG |:VERS |  RSSDCNT    |
*     +------+------+-------------+------+------+-------------+
*  10 |         RSSMSGN           |///////////////////////////|
*     +---------------------------+---------------------------+
*
*** RSSBK - RECORDING SYSTEM SERVICE BLOCK
          
*** Overlay for RSSVN00M in RSSBK
*
*                                               +-------------+
*   0 ...                                     6 |  RSSV00MN   |
*                                               +-------------+
*   8
*
*** Overlay for RSSVN00M in RSSBK
          
*** Overlay for RSSMSGN in RSSBK
*
*
*** Overlay for RSSMSGN in RSSBK
 
 
  RSSBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
RSSBLEN        0018 00000018
RSSDATA        0018
RSSDCNT        000E
RSSFLAG        000C
RSSFRESZ       000A
RSSMSGN        0010
RSSNEXT        0000
RSSNOMON       000C 20
RSSRACNT       0009 00000001
RSSRCNFG       0009 00000004
RSSRID         0009
RSSRINC        000C 40
RSSRINIT       000C 80
RSSRIOER       0009 00000002
RSSRSYMP       0009 00000003
RSSRTAB        0009 000000FF
RSSSIZE        0018 00000003
RSSUSCNT       0004
RSSVERS        000D
RSSVN00        000D 00000000
RSSVN00M       0006
RSSVN01        000D 00000001
RSSV00DA       0010
RSSV00HL       0010 00000010
RSSV00MN       0006
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:54:36 EDT.
Copyright IBM Corporation, 1990, 2022