OA61750: NEW FUNCTION - SUPPORT JES2 CHECKPOINT VERSIONS IN 64-BIT STORAGE

Obtain the fix for this APAR.

APAR status

• Closed as new function.

Error description

• The function provided by this APAR will move the non-live
  checkpoint versions from JES2 data space storage to 64-bit
  JES2 private storage. The storage for the checkpoint versions
  will also be shared so that JES Job Information SSI 71
  Checkpoint Version Information Services can supply a DSERV
  (IAZDSERV) copy of the JES2 checkpoint data to applications,
  utilizing those checkpoint versions in 64-bit storage.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All users of HJE77D0.                                        *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * Support JES2 checkpoint versions in                          *
  * 64-bit storage.                                              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  JES2 checkpoint versions are used to provide a stable copy
  of the job and output queues when processing data requests
  from applications. Prior to this change, a checkpoint version
  starts with a copy of the checkpoint data in a data space,
  and uses shared pages and copied pages to build additional
  copies of the data.  With this new function APAR change, the
  checkpoint version is moved into 64-bit private storage.
  Pages are always shared, eliminating the copying of pages,
  resulting in lower CPU usage and fewer copies of the
  checkpoint pages.
  

Problem conclusion

Temporary fix

Comments

• TYPE/RESTART (WARM) IPL/REQUIRED (YES) CLPA (YES)
  
  CLPA is needed only if HASCxxxx modules currently reside in
  the pageable link pack area (PLPA).
  
  JES2 checkpoint versions are obtained using SSI 71 (JES Job
  Information Service) subfunction 4 (SSJIFOBT - obtain a
  version).  The IAZDSERV macro contains the pointers to the
  data areas in the checkpoint version.  The existing versions
  1 through 9 of the IAZDSERV macro (DSERV DSECT) are defined
  using 31-bit addresses and ALETs to access the checkpoint
  data.  To help ease migration, a new version 10 IAZDSERV
  (DSERVX DSECT) was introduced in z/OS 2.4 (HJE77C0) with
  64-bit addresses and ALETs to access the checkpoint data.
  With z/OS 2.4, applications can use a pre-version 10
  IAZDSERV to access a checkpoint version and continue using
  31-bit pointers.  However, applications can start their
  migration to the new 64-bit checkpoint version by passing in
  a version 10 IAZDSERV and access the checkpoint version data
  using the 64-bit pointers (even though the data areas are in
  31-bit storage).  JES2 SSI code that accesses a checkpoint
  version was updated to use the new version 10 (64-bit)
  DSERVX DSECT.
  
  Note that when a pre-version 10 IAZDSERV is passed to the
  checkpoint version SSI, if the version storage for an area
  is backed by 64-bit storage, the corresponding pointer to
  the area will return a value of x'7FFFBAD' with an ALET
  value of 0. The return code (SSOBRETN) will be set to 4
  with reason code (SSJIRETN) of 40.
  
  When OA61229 moved the track group map (TGM) to 64-bit
  storage, the IAZDSERV pointer DSRVTGPT started returning zero
  when a pre-version 10 IAZDSERV was passed, and the return and
  reason codes (SSOBRETN and SSJIRETN, respectively), were set
  to zero.  Now, with OA61750 applied, the DSRVTGPT field will
  be set to x'7FFFFBAD' and SSOBRETN will be set to 4 and
  SSIJRETN will be set to 40.
  
  
  The following specific pointers are impacted by this change:
  DSRVJOPT - Pointer TO JOT
  DSRVJQPT - Pointer TO JQE
  DSRVQSPT - Pointer TO QSE
  DSRVHCPT - Pointer TO HCT
  DSRVJNPT - Pointer TO JNT
  DSRVJXPT - Pointer to JQX
  DSRVJTPT - Pointer to JQE track group extension
  DSRVDAPT - Pointer to DAS
  DSRVWQST - Pointer to WQPOS
  DSRVOXPT - Pointer to JOX
  DSRVTGPT - Pointer to TGM
  DSRVZJPT - Pointer to ZJC
  
  
  The information in the following MVS manuals/publications
  is missing/incorrect:
  
  1.SA38-0679-50 z/OS 2.5 MVS Using the Subsystem Interface
                                                   (for HBB77D0)
  2.SA38-0665-50 z/OS 2.5 MVS System codes         (for HBB77D0)
  
  
  Updates were made to the MVS publications listed
  above to describe the new support delivered via this APAR.
  Refer to the latest version of the manuals on IBM DOCS to
  obtain the most current information on this function.
  
  Refer to Chapter 3, SSI function codes your program can
  request, SSI function code descriptions, JES job information
  services - SSI function code 71 section on Checkpoint Version
  Information Service, in z/OS 2.5 MVS Using the Subsystem
  Interface (SA38-0679-50) for information on how this APAR
  affects the SSI used to request checkpoint versions:
  https://www.ibm.com/docs/en/SSLTBW_2.5.0/
  com.ibm.zos.v2r5.ieaf200/checkoutpar.htm
  
  The updates document a new version 10 IAZDSERV parameter
  list that is used to request checkpoint version information
  that is now located in 64-bit storage. Look for the definition
  of the new DSRXxxxx fields for a description of the new
  version 10 parameter list fields.
  
  Also note the new paragraph entitled "Checkpoint versions
  information service, IAZDSERV contents" for a discussion of
  the indicators returned in a pre-version 10 (31-bit) IAZDSERV
  parameter list when a 64-bit pointer cannot be set in the
  31-bit format IAZDSERV.
  
  
  APAR OA61750 prereq's (and sup's) for FMID HJE77D0:
  Pre's: DA61593 DA60777 DA62436 DA61231
  
  ×**** PE22/10/19 FIX IN ERROR. SEE APAR OA63943  FOR DESCRIPTION
  ×**** PE23/05/22 FIX IN ERROR. SEE APAR OA64913  FOR DESCRIPTION
  

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UJ09134

Modules/Macros

• HASPRAS  $CVCB    HASCOFST $MODULE  $DTECKDA HASPSPIN HASPIRA
  HASPCKVR HASCSIJP HASPSSRV HASPSTAB HASPSASR HASCSISC $DSERV
  HASPNUC  HASPCKDS HASMTABL $KIT     $SXADDR  $AUXCB   $HASPEQU
  HASCSIRQ HASMITAB HASPIRDA HASPCKPT HASPSERV HASPIRSI $HCCT
  HASPCFSI $SCID    HASJSPLR $CKW     HASCSRAX HASPTERM HASPTABS
  HASPJQS  HASCSIJI HASMKIT  $HCT     HASPCFFC HASPCFRD $QJQE
  HASPCSV  HASMCKFM HASMCVCB HASCSRIC HASPCFE  HASPXCF  HASPSXIT
  $PGSRVC  $PCTAB   $CIRWORK HASMCADR HASPEVTL $CAL     HASPMSG
  $CALL    HASCSRIP $DTELIM  HASMDTE4 HASPJOS  $CK      HASMHCCT
  HASPCFLE HASMPCE1 HASMCKW  HASPIRMA $CADDR   HASPCKDA HASMSXAD
  HASMSCID
  

Fix information

• Fixed component name

  JES2

• Fixed component ID

  5752SC1BH

Applicable component levels

• R7D0 PSY UJ09134

     UP22/09/09 P F209  

Fix is available

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