PI19035: GPF IN SYSTEMDATA GETCPUUTILIZATION OCCURS ON Z/OS WAS NODEAGENT

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• The PMI code is collecting CPU utilization information.  It
  calls QueryMetrics which calls WLM function IWMWSYSQ.  There is
  a timing window, where when a WLM policy is activated, WLM can
  return back zero's for un-used CPU and used CPU.   As part of
  the WLM policy activation process , WLM to clears out the
  workload performance history.  If the QueryMetrics call that
  PMI code makes is done shortly after the policy activation, WLM
  may not have accumulated any new history data yet so all of the
  performance information is zero.  When the PMI code tries to do
  calculations using these zero values, it causes GPF.
  
  
  Java call stack for the GPF is:
  com/ibm/ws/pmi/server/system/SystemData.
     getCpuUtilization(Native Method)
  com/ibm/ws/pmi/server/system/SystemData.
     access200(SystemData.java:61(Compiled Code))
  com/ibm/ws/pmi/server/system/SystemDataCpuUtilization.
     get(SystemData.java:191(Compiled Code))
  com/ibm/ws/pmi/server/system/SystemData.
     getCpuUtilization(SystemData.java:221(Compiled Code))
  com/ibm/ws/pmi/server/modules/SystemModuleSystemPerfData.
     updateStatistic(SystemModule.java:83(Compiled Code))
  com/ibm/ws/pmi/server/data/SpdLongExternal.updateExternal
     (SpdLongExternal.java:88(Compiled Code))
  com/ibm/websphere/pmi/server/PmiAbstractModule.
     update(PmiAbstractModule.java:1342(Compiled Code))
  com/ibm/websphere/pmi/server/PmiAbstractModule.updateStatistics
     (PmiAbstractModule.java:1365(Compiled Code))
  com/ibm/ws/pmi/server/ModuleItem.updateStatisticsForStatsTree
     (ModuleItem.java:584(Compiled Code))
  com/ibm/ws/pmi/server/ModuleItem.getStats
     (ModuleItem.java:713(Compiled Code))
  com/ibm/ws/pmi/server/PmiRegistry.getStats
     (PmiRegistry.java:928(Compiled Code))
  com/ibm/ws/pmi/server/PmiRegistry.getStats
     (PmiRegistry.java:968(Compiled Code))
  com/ibm/ws/pmi/server/PmiCollaboratorImpl.getStatsArray
     (PmiCollaboratorImpl.java:348(Compiled Code))
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM WebSphere Application       *
  *                 Server V7.0                                  *
  ****************************************************************
  * PROBLEM DESCRIPTION: The GPF event is occuring on WebSphere  *
  *                      Application Server for z/OS from PMI    *
  *                      Native code at NodeAgent Process.       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The GPF event is occuring from PMI's native code when WLM
  policy which has been configured on a z/OS system get
  activated and at the same time PMI tries to get CPU Utilization
  of system for the SystemModule's counters. This is due to
  InValid System's CpuUsage value returned from z/OS System when
  WLM policy get activated.
  

Problem conclusion

• The PMI Native code which is returning incorrect System's
  cpuUsage when WLM policy get activated and causing GPF event
  has been handled and so avoiding the issue.
  
  APAR PI19035 is currently targeted for inclusion in Fix Pack
  7.0.0.33 of WebSphere Application Server.
  
  Please refer to URL:
  //www.ibm.com/support/docview.wss?rs=404&uid=swg27006970
  for Fix Pack availability.
  

Temporary fix

Comments

APAR Information

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

  PM99345

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

Modules/Macros

• BBGUBINF BBOUBINF
  

Fix information

• Fixed component name

  WEBSPHERE FOR Z

• Fixed component ID

  5655I3500

Applicable component levels

• R700 PSY UI18561

     UP14/06/21 P F406

Fix is available

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