OA37649: WLM FAILS TO UNPARK CPS AFTER AN LPAR IS SOFT CAPPED.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Processors may remain parked following a period of WLM Soft
  Capping. RMF reports will show 1 LOW CP unparked but other LOW
  CPS will remain parked.
  During the WLM Capping, all LOW CPS will be parked. The problem
  will occur when the final LOW CP has the LCCAPARK flag set
  indicating it is parked, but it continues to dispatch. When WLM
  is ready to start unparking CPS during or following the capping
  it continues to try to unpark the same LOW CP that has
  LCCAPARK set, but is still dispatching. This prevents WLM from
  uncapping additional CPS.
  

Local fix

• Change the LPAR weighting so that the LPAR guaranteed
  share of the CEC is closer to the defined capacity limit. This
  will reduce the LPARs dependency on LOW CPS and minimize the
  problem.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: Systems running HBB7760 and above.           *
  ****************************************************************
  * PROBLEM DESCRIPTION: WLM FAILS TO UNPARK CPS AFTER AN LPAR   *
  *                      IS SOFT CAPPED.                         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Processors may remain parked following a period of WLM Soft
  Capping. RMF reports will show 1 LOW CP unparked but other LOW
  CPS will remain parked.
  During the WLM Capping, all LOW CPS will be parked. The problem
  will occur when the final LOW CP has the LCCAPARK flag set
  indicating it is parked, but it continues to dispatch. When WLM
  is ready to start unparking CPS during or following the capping
  it continues to try to unpark the same LOW CP that has
  LCCAPARK set, but is still dispatching. This prevents WLM from
  uncapping additional CPS.
  

Problem conclusion

• When a vertical low CPU dispatches work, turn off LCCAPARK.
  

Temporary fix

Comments

• D/T2827
  

APAR Information

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

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

  UA63071 UA63070 UA63072

Modules/Macros

• IEAVEDS0
  

Fix information

• Fixed component name

  SUPERVISOR CONT

• Fixed component ID

  5752SC1C5

Applicable component levels

• R760 PSY UA63070

     UP11/11/23 P F111

• R770 PSY UA63071

     UP11/11/23 P F111

• R780 PSY UA63072

     UP11/11/23 P F111

Fix is available

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