IT21883: IBM MQ Appliance: The status command shows high memory utilization

APAR status

• Closed as program error.

Error description

• The status command in the MQ Appliance reports high memory
  usage.  For example:
  
  mqa(mqcli)# status QMNAME
  QM(QMNAME)                             Status(Running)
  CPU:                                              175.57%
  Memory:                                        25814MB
  ...
  

Local fix

• Although this issue should not affect the operation of the queue
  manager, it is possible to reset the statistics by restarting
  the queue manager.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of the IBM MQ Appliance status command or those who
  consume statistics published to the new system topics under
  $SYS/MQ/INFO/QMGR may be affected by this issue.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The value of statistic CPU - QMgrSummary - RAM total bytes is
  exposed via the IBM Appliance status command under the "Memory"
  field and by statistics published under system topic
  $SYS/MQ/INFO/QMGR.  The value of this statistic may not be
  accurate.
  
  IBM MQ tracks memory usage internally and a code defect meant
  that a small amount of memory that had been freed was not being
  tracked.  Over a period of time, this defect caused the amount
  of memory reported as in use by IBM MQ to be much larger than
  the amount it was actually using.
  
  This issue only occurred when an IBM MQ thread ended and so the
  problem may not be as noticeable on systems where connection
  turnover is low.
  

Problem conclusion

• The code was modified so that memory which had been freed by IBM
  MQ was properly accounted for.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.8
  v9.0 CD    9.0.4
  v9.0 LTS   9.0.0.3
  
  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

  IBM MQ APPL M20

• Fixed component ID

  5725S1400

Applicable component levels

• R800 PSY

     UP