IT20487: MQ Explorer process creates a dump reporting an out of memory error

APAR status

• Closed as program error.

Error description

• The IBM MQ Explorer generates dump files.
  
  Running a memory analysis tool against these core dumps shows
  the following:
  
  Possible failure detected in module
  C:\Windows\System32\ntdll.dll
  Out of memory detected
  
   Executable: C:\Program Files\IBM\WebSphere
  MQ\bin64\MQExplorer.exe
  
       52: java/util/Hashtable.rehash ()V(564)
           51: java/util/Hashtable.put
  (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;(628)
           50:
  com/ibm/mq/explorer/ui/internal/controls/ExtTableGreyCellManager
  .getGreyCellListFromHashtable
  (Lcom/ibm/mq/commonservices/internal/trace/Trace;Lcom/ibm/mq/exp
  lorer/ui/extensions/MQExtObject;)Ljava/util/ArrayList;
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of
    - IBM MQ Explorer V8.0
    - IBM MQ Explorer V9.0
  
  
  Platforms affected:
  Linux on x86, Linux on x86-64, Windows
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The IBM MQ Explorer displays MQ objects in its content view
  tables.  One of the data structures that is used to determine
  what is displayed in each content view table is the grey cell
  Hashtable.  This Hashtable records which cells for each
  individual object shown should be greyed out.
  
  Cells are greyed out if the property, which would otherwise be
  displayed in that cell, is not applicable to that object.  For
  example, the "Remote queue" property is not valid for a local
  queue, so this cell is greyed out for any local queues displayed
  in the queue content view table.
  
  Entries are added to this grey cell Hashtable each time a new MQ
  object is created.
  
  Entries representing each MQ object are also added to this
  Hashtable each time the content view table is redrawn.  Each
  time a redraw event happens the internal table representing the
  objects in the content view table is cleared and regenerated.
  Examples of when this happens include when the table is
  refreshed, when a filter is applied or when moving between types
  of objects.
  
  However, the grey cell Hashtable was not cleared when the
  internal object table was cleared, and entries were not removed
  when MQ objects were deleted.   This resulted in the Hashtable
  growing over time, eventually leading to an out of memory event
  if the MQ Explorer was left open for sufficient duration.
  

Problem conclusion

• The IBM MQ Explorer code has been updated to remove the
  appropriate entry from the grey cell Hashtable when an MQ object
  is deleted.
  
  It has also been update to clear the contents of the grey cell
  Hashtable each time the internal representation of the list of
  objects in the MQ Explorer table is cleared.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.9
  v9.0 CD    9.0.5
  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

  WMQ BASE MULTIP

• Fixed component ID

  5724H7251

Applicable component levels

• R800 PSY

     UP