IT32393: Object damage reported when queue file size reaches 2 TB

APAR status

• Closed as program error.

Error description

• Queue manager reports object damage for a queue when the queue
  file size reaches 2 TB. The following
  failure data capture (FDC) records were generated.
  
  2020/03/10 12:53:46.767065-5 amqrmppa 213292 562 AQ115020
  aqhResizeSpaceMap STOP
  2020/03/10 20:30:46.689649-5 amqrmppa 213292 564 AQ066010
  aqhAllocateSpace  arcE_OBJECT_DAMAGED
  2020/03/10 20:30:49.065654-5 amqrmppa 213292 564 AQ060020
  aqhLoadMsgChain   arcE_OBJECT_DAMAGED
  2020/03/10 20:30:51.415984-5 amqrmppa 213292 564 AQ056010
  aqhLoadQueue      arcE_OBJECT_DAMAGED
  

Local fix

• Set a MAXDEPTH (and MAXMSGL if necessary) for the queue to
  prevent it from growing to 2TB.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users using very large queue files where the queue file size is
  expected to grow to 2 TB
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A defect in MQ queue object buffer handling caused the object
  damage when the queue file size reached 2 TB limit.
  

Problem conclusion

• * MQ versions older than MQ 9.1.5
  
  A design limitation of the queue implementation prior to MQ
  9.1.5 means that the queue object with 2TB size can only be
  supported by disabling the queue buffering for non persistent
  messages.
  
  Procedure to disable queue buffering for non persistent
  messages.
  
  - Apply the fix for the APARs IT29354 and IT32393.
  
  - After applying the fix, set the DefaultQBufferSize to 0 and
  then recreate the queue
    which is expected to consume 2 TB.
  
  TuningParameters:
     DefaultQBufferSize=0
  
  After recreating the queue, remove the tuning parameter or set
  the DefaultQBufferSize to the
  required value and then restart the QM so that other
  newly-defined queues will be created with default buffer
  size or the user defined buffer size( > 0). Altering this
  parameter does not affect queues that have already been defined.
  
  The buffer length set for the queue can by checked by dumping
  the queue details using the amqldmpa
  command.
  
  Command: amqldmpa -m TESTQMGR  -c A -u 1 -q  TESTQ -d 15 -f
  /var/mqm/trace/TESTQ.dmp.out
  
  Attribute name : StgClass.MaxQBufferLength
  
  Examples:
  
  StgClass.MaxQBufferLength 0              <---   0 byte
  StgClass.MaxQBufferLength 4194304        <---   4 MB
  StgClass.MaxQBufferLength 131072         <---   128 KB (Default)
  
  
  * MQ version 9.1.5
  
  MQ 9.1.5 code has been modified to prevent the queue manager
  encountering the problem.
  Apply the fix for this APAR to prevent the queue manager from
  encountering the object damage problem if a queue file reaches
  2TB.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.16
  v9.0 LTS   9.0.0.11
  v9.1 LTS   9.1.0.7
  v9.x CD    TBC.
  
  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 BASE MP

• Fixed component ID

  5724H7251

Applicable component levels