PI47893: LARGE NUMBER OF ACCESSES TO CSQ.OBJ_B_QUEUE USING PLAN CSQ5R710

APAR status

• Closed as duplicate of another APAR.

Error description

• The initial symptom was 800,000 DB2 SMF records being cut per
  hour as a result of MQ activity.  DB2 traces tracked this to
  plan CSQ5R710 and identified very many sequences of
  open/fetch/close on CSRQUEUE cursor in CSQ5AROB.
  
  Periodically, the queue-manager will check in DB2 for any new
  queues which have been created. It should only check for new
  queues since the last time it checked. However, if a queue
  which is not a temporary dynamic queue is deleted, the 'last
  time checked' time-stamp will be reset to the time the
  queue-manager was started (this change was made by PM79700).
  This means that if there are shared dynamic queues being
  deleted frequently (e.g. due to MQCO_DELETE_PURGE being used)
  this can cause the issue seen here with a large number of
  accesses to CSQ.OBJ_B_QUEUE using plan CSQ5R710).
  .
  Additional keywords:
  SQL performance
  

Local fix

• No local fix
  

Problem summary

Problem conclusion

Temporary fix

Comments

• Closing duplicate of PI52685
  

APAR Information

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

  PI44165

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

Fix information

Applicable component levels