PH50123: EXCESSIVE CONSUMPTION OF SUBPOOL228 KEY 2 COMMON STORAGE

APAR status

• Closed as program error.

Error description

• The client experiences multiple system issues caused by a lack
  of common storage.  Dump analysis reveals that WebSphere servers
  were consuming very many WLM performance blocks which reside in
  subpool 228.  The WebSphere controller region runs in key 2.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server V9.0 for z/OS                        *
  ****************************************************************
  * PROBLEM DESCRIPTION: WebSphere Application Server for z/OS   *
  *                      allocated large amount of common        *
  *                      storage.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The Controller Region uses WLM Performance Blocks (PB).  A
  pool  is managed and extended as needed by calling WLM service
  IWMMCREA. Each call to WLM for extension is to obtain 20
  elements which are backed in common storage.
  There is no limit to the number of times the above pool may be
  extended.  The Controller Region obtains a PB for each ACRW
  queued.  From analysis by WLM it was determined that a
  Controller Region had extended the PB pool 464 times.  We
  obtain 20 PBs per call to WLM.  That totaled 9280 PBs at the
  time a dump was taken.
  

Problem conclusion

• Code has been updated to disable the extension of the WLM
  Performance Blocks pool during stop processing.
  Also, a limit to the number of extensions has been implemented
  to prevent excessive use of common storage.
  
  The fix for this APAR is targeted for inclusion in fix packs
  9.0.5.16 and 8.5.5.24.
  For more information, see 'Recommended Updates for
  WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

Temporary fix

Comments

APAR Information

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

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

Fix information

• Fixed component name

  WEBSPHERE FOR Z

• Fixed component ID

  5655I3500

Applicable component levels