IC73447: MEMORY LEAK IN V7.0 WEBSPHERE MQ CLASSES FOR JMS WHEN TRACING IS ENABLED

WebSphere MQ V7.0 Fix Pack 7.0.1.6
WebSphere MQ V7.0.1 for i5/OS Fix Pack 7.0.1.6

APAR status

• Closed as program error.

Error description

• When the V7.0 WebSphere MQ classes for JMS tracing is enabled
  for a long time, an OutOfMemory error is observed. The
  generated heap dump shows the following leak suspect:
  
  246,668,272 (93%) [152] 1 com/ibm/rds/RDSCache 0xc216e8
  246,668,120 (93%) [72] 4 java/util/logging/Logger 0xc21658
  246,597,112 (93%) [24] 3 java/util/logging/LogManager 0x98f860
  246,577,920 (93%) [40] 1 java/util/Hashtable 0xa0c298
  246,577,880 (93%) [784] 98 array of
  java/util/Hashtable$Entry 0x21d3120
  246,435,320 (93%) [32] 3 java/util/Hashtable$Entry 0x1259848
  246,434,344 (93%) [72] 6 java/util/logging/Logger 0x125d398
  246,434,152 (93%) [80] 1 array of
  java/util/logging/Handler 0x1262d80
  246,434,072 (93%) [88] 12 java/util/logging/FileHandler
  0x1264d38
  246,409,784 (93%) [64] 5
  com/ibm/msg/client/commonservices/j2se/trace/HumanFormatter
  0x1264d90
  246,368,608 (93%) [32] 4
  
  com/ibm/msg/client/commonservices/j2se/trace
  /HumanFormatter$FastHashMap
  0x12689c0
  246,368,192 (93%) [48] 2 java/util/HashMap 0x1289fc8
  246,368,128 (93%) [4,194,320] 417,238 array of
  java/util/HashMap$Entry 0xe905588
  
  This issue is observed when the using the V7.0 WebSphere MQ
  classes for JMS tracing with wrapping options set and the
  output destination set to a file.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of the V7.0 WebSphere MQ classes for
  JMS who enable the WebSphere MQ classes for JMS trace.
  
  Platforms affected:
  All Distributed (iSeries, all Unix and Windows) +Java
  ****************************************************************
  PROBLEM SUMMARY:
  One of the data structures used for maintaining the cache for
  WebSphere MQ JMS tracing was not being cleared. This led to a
  slow accumulation of objects in the java heap, which eventually
  led to a OutOfMemory error when tracing was left running for a
  long length of time.
  

Problem conclusion

• The code fix associated with this APAR ensures that the number
  of objects in the cache do not overflow, and hence ensures that
  the java heap is not filled up while writing the trace output.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
                     v7.0
  Platform           Fix Pack 7.0.1.6
  --------           --------------------
  Windows            U200328
  AIX                U840698
  HP-UX (PA-RISC)    U841555
  HP-UX (Itanium)    U841560
  Solaris (SPARC)    U841556
  Solaris (x86-64)   U841562
  iSeries            tbc_p700_0_1_6
  Linux (x86)        U841557
  Linux (x86-64)     U841561
  Linux (zSeries)    U841558
  Linux (Power)      U841559
  
  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 WINDOWS V7

• Fixed component ID

  5724H7220

Applicable component levels

• R700 PSY

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