IV30481: WMQ JMS - MSGTOKEN TO GET THE MESSAGE AFTER AN INCREASE IN THE BUFFER SIZE.

WebSphere MQ V7.5 Fix Pack 7.5.0.1
WebSphere MQ V7.0 Fix Pack 7.0.1.10
Fix Pack 7.1.0.3 for WebSphere MQ V7.1

APAR status

• Closed as program error.

Error description

• When using the WebSphere MQ classes for JMS/Java  client to get
  a message, and that message is over 4096 bytes then a
  TRUNCATED_MSG_FAILED return code is returned by the queue
  manager. In this situation the client will automatically resize
  the buffer used to get the message and issue another MQGET using
  the message id and correlation id obtained in the first MQGET.
  *
  Additional Keywords:
  MsgId CorrelId MQMO_MATCH_MSG_ID MQMO_MATCH_CORREL_ID
  z/OS performance cpu slow curdepth
  CSQI004I CSQP020I
  .
  There have been some follow-on APARs to adjust how this logic
  works with specific get options (IV49971, IC97121 and IT00404).
  To ensure that the full implementation is picked up, the
  7.0.1.13 fixpack level should be used.
  

Local fix

• For queues on z/OS, overhead can be somewhat reduced by
  setting INDXTYPE for the queue as advised by the CSQI004I
  message for the queue in the MSTR joblog.
  .
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of the WebSphere MQ classes for JMS and
  WebSphere MQ classes for Java, including:
  
  - The WebSphere MQ V7 classes for JMS.
  - The WebSphere MQ V7 classes for Java.
  - The WebSphere MQ V7 Resource Adapter.
  - The WebSphere Application Server V7 WebSphere MQ messaging
  provider.
  - The WebSphere Application Server V8 WebSphere MQ messaging
  provider.
  - The WebSphere Application Server V8.5 WebSphere MQ messaging
  provider.
  - The WebSphere Application Server V6.1 WebSphere MQ messaging
  provider who have configured the WebSphere variable
  MQ_INSTALL_ROOT to point to a WebSphere MQ V7 installation.
  
  who are getting messages that are larger than 4096 bytes.
  
  Platforms affected:
  All Distributed (iSeries, all Unix and Windows) +Java +Java zOS
  ****************************************************************
  PROBLEM SUMMARY:
  The WebSphere classes for JMS/Java will execute 2 MQGET calls if
  the message to retrieve is over 4096 bytes. The first call to
  MQGET will return MQRC_TRUNCATED_MSG_FAILED indicating that the
  message buffer supplied (4096) is too small. The second MQGET
  alters the message buffer to be large enough for the message but
  uses the message ID and correlation ID to obtain the same
  message.
  
  As message ID and correlation ID might not be unique then it is
  possible that a different message is returned. This could then
  cause another MQRC_TRUNCATED_MSG_FAILED as the buffer size is
  now incorrect for this new message.
  

Problem conclusion

• This APAR solves the problem by making sure that the second
  MQGET is issued with the MQMO_MATCH_MSG_TOKEN option. The
  MessageToken uniquely identifies the message within the WMQ
  Queue Manager, this will ensure that the same message is
  retrieved on the second MQGET.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
                     v7.0
  Platform           Fix Pack 7.0.1.10
  --------           --------------------
  Windows            U200352
  AIX                U853055
  HP-UX (PA-RISC)    U853082
  HP-UX (Itanium)    U853087
  Solaris (SPARC)    U853083
  Solaris (x86-64)   U853089
  iSeries            7.0.1.10
  Linux (x86)        U853084
  Linux (x86-64)     U853088
  Linux (zSeries)    U853085
  Linux (Power)      U853086
  zOS                7.0.1.10
  
                     v7.1
  Platform           Fix Pack 7.1.0.3
  --------           --------------------
  Windows            7.1.0.3
  AIX                7.1.0.3
  HP-UX (Itanium)    7.1.0.3
  Solaris (SPARC)    7.1.0.3
  Solaris (x86-64)   7.1.0.3
  iSeries            7.1.0.3
  Linux (x86)        7.1.0.3
  Linux (x86-64)     7.1.0.3
  Linux (zSeries)    7.1.0.3
  Linux (Power)      7.1.0.3
  zOS                7.1.0.3
  
  Platform           v7.5
  --------           --------------------
  Multiplatforms     7.5.0.1
  
  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 AIX V7

• Fixed component ID

  5724H7221

Applicable component levels

• R701 PSY

     UP