OA44913: RSM GLOBAL STEAL DOES NOT STEAL DISCARDED KEEPREAL YES FRAMES BACKING HVSHARE WHEN XCF CRITICAL PAGING IS ENABLED

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• RSM global steal processing ignores frames backing high virtual
  shared storage when XCF criticalpaging is enabled even after the
  storage was requested to be discarded and the real kept with
  IARV64 Request=DISCARDDATA,KEEPREAL=YES. This can cause an
  increase in total real storage usage and other frames to be
  paged out in order to bring the system available frame count
  back up to the threshhold when IARUOGBS is scheduled.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of HBB7770 and up with Critical paging *
  *                 enabled.                                     *
  ****************************************************************
  * PROBLEM DESCRIPTION: Real frames backing High virtual shared *
  *                      pages discarded with IARV64             *
  *                      DISCCARDDATA,KEEPREAL=YES are not       *
  *                      stolen during global steal when         *
  *                      critical paging is enabled.             *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The Couplexx parmlib member specified FUNCTIONS
  ENABLE(CRITICALPAGING). RSM global steal processing skipped
  stealing frames that backed high virtual shared storage, even
  when the pages were released with IARV64 DISCARDDATA,
  KEEPREAL=YES.
  

Problem conclusion

• When critical paging is enabled, RSM global steal processing
  will support the stealing of frames backing high virtual shared
  storage if the pages have been discarded.
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

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

  UA74194 UA74195 UA74196 UA74197

Modules/Macros

• IAXUO
  

Fix information

• Fixed component name

  RSM - REAL STOR

• Fixed component ID

  5752SC1CR

Applicable component levels

• R770 PSY UA74194

     UP14/07/30 P F407 Ž

• R78H PSY UA74197

     UP14/07/30 P F407 Ž

• R780 PSY UA74195

     UP14/07/30 P F407 Ž

• R790 PSY UA74196

     UP14/07/30 P F407 Ž

Fix is available

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