PH23416: HIGH CPU OBSERVED WHEN RUNNING OSGI TRANSACTIONS INVOLVING MQ UNDER CICS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• High CPU is observed when running OSGi transactions involving
  MQ under CICS
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 9       *
  *                 Release 1 Modification 0 and Release 2       *
  *                 Modification 0.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: High CPU occurs when using OSGi         *
  *                      transactions in CICS that make MQI      *
  *                      calls to MQ.                            *
  ****************************************************************
  During execution of a CICS transaction calling MQ, CSQMCPRH
  calls IFAUSAGE to register/deregister MQ usage recording for
  that transaction.
  While running entirely on an L8 or T8 TCB all calls for the
  transaction occurred on the same TCB, however for OSGi
  transactions the MQ TRUE is called on a T8 TCB, except for the
  end thread processing, which is called on the L8 TCB.
  This led to errors when IFAUSAGE was called, resulting in a
  build up of TCA control blocks and increased CPU usage.
  

Problem conclusion

• CSQMCPRH is changed to track whether the TCB has registered with
  IFAUSAGE, allowing transactions that call MQ from multiple
  threads to issue the expected IFAUSAGE calls.
  

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:

  UI71287 UI72369

Modules/Macros

• CSQ3RRSM CSQMCPRH
  

Fix information

• Fixed component name

  IBM MQ Z/OS V9

• Fixed component ID

  5655MQ900

Applicable component levels

• R100 PSY UI72794

     UP20/12/08 P F012

• R200 PSY UI72795

     UP20/12/08 P F012

Fix is available

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