PH69660: MQ 930 INCORRECT PERFORMANCE EVENT MESSAGE ISSUED

APAR status

• Closed as program error.

Error description

• Check for a High Service Time may give a negative result. When
  multiple threads are putting and/or getting from the queue at
  the same time, a putting application may get suspended after
  obtaining the current time to check for a high service interval.
  If another thread updates the queue's last service time while
  the putter is suspended, then the check for a high service time
  may give a negative result. This is interpreted as a very high
  service time and the event message is incorrectly issued.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 9       *
  *                 Release 3 Modification 0 and Release 4       *
  *                 Modification 0.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Queue service interval high events may  *
  *                      be produced when multiple               *
  *                      applications are putting to the same    *
  *                      empty queue.                            *
  ****************************************************************
  With performance events enabled, and a high service
  interval set on the queue. If there are multiple puts to the
  queue within a short period of time, CSQMIAPM may wait for the
  object latch for the queue which may result in the
  calculation for elapsed time to return a negative value into an
  unsigned value. This results in the service interval high
  performance
  events being produced more frequently than expected.
  

Problem conclusion

• The processing has been altered to correctly calculate the time
  used prior to issuing the events to correctly deal with multiple
  putting applications waiting on the same object latch.
  

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:

  UO07005 UO07006

Modules/Macros

• CSQMIAPM
  

Fix information

• Fixed component name

  IBM MQ Z/OS V9

• Fixed component ID

  5655MQ900

Applicable component levels