IV55876: Synchronization issues with xlsThreadTermination/xcsDecrementQuickCellUseCount

WebSphere MQ V7.5 Fix Pack 7.5.0.4

APAR status

• Closed as program error.

Error description

• Synchronization issues may happen in systems with high MQ
  connection/disconnections which leads to incorrect quickcell
  usecount. FDCs will be generated indicating the corrupted
  quickcells. Following FDCs with probe ids XC476004,XC034070,
  XC302005, XC014030 may be generated. The FDCs will have the
  function stack
   MQM Function Stack
  ExecCtrlrMain
  zxcProcessMessage
  zxcMQIRequest
  zxcConnectAgent
  xlsAbandonRecoveryToken
  xcsDecrementQuickCellUseCount
  xcsFFST
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue may occur on machines which has high number MQ
  connections and disconnections.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM SUMMARY:
  The synchronizing problem occurred because the quickcell
  usecount was not being calculated correctly.
  

Problem conclusion

• The code changes have been made to include additional checks for
  the PID and prevent a partially initialized data structure from
  being used during MQCONN, thus eliminating the synchronization
  issue.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v7.5       7.5.0.4
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

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

  WMQ AIX V7

• Fixed component ID

  5724H7221

Applicable component levels

• R701 PSY

     UP