PM71430: PUBSUB MESSAGES STUCK ON WEBSPHERE APPLICATION SERVER SERVICE INTEGRATION BUS PUBLICATION POINT

PM71430; 8.0.0.5: pubsub messages stuck on WebSphere Application Server SIB
7.0.0.27: WebSphere Application Server V7.0 Fix Pack 27
8.5.0.2: WebSphere Application Server V8.5 Fix Pack 2
8.0.0.6: WebSphere Application Server V8.0 Fix Pack 6

APAR status

• Closed as program error.

Error description

• A JMS application publishes messages to WebSphere Application
  Server Service Integration Bus publication point. The published
  messages are delivered to the consumers successfully but the
  messages still remain on the publication point. This leads to
  a build up of messages on the destination. The following errors
  are written to the SystemOut.log:
  
  CWSIA0067E: An exception was received during the call to the
  method JmsMsgProducerImpl.sendMessage (#4): com.ibm.ws.sib.
  processor.exceptions.SIMPLimitExceededException:CWSIP0251E:
  The destination XXXTopicSpace on messaging engine
  XYZ is not available because the high limit 50,000 for the
  number of messages for this destination has already been
  reached..
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  Users of the default messaging provider     *
  *                  for IBM WebSphere Application Server        *
  ****************************************************************
  * PROBLEM DESCRIPTION: PubSub messages are stuck on WebSphere  *
  *                      Application Server Service              *
  *                      Integration Bus                         *
  ****************************************************************
  * RECOMMENDATION:  None                                        *
  ****************************************************************
  In the publish/subscribe domain, the messages produced on
  topics move across messaging engines if there are more than
  one messaging engine in an Application Server environment.
  This allows consumers running on remote messaging engines to
  receive messages. The messaging engine where messages are
  produced is called the source messaging engine and the
  messaging engine where messages are received is called the
  target messaging engine. In this communication, when the
  target messaging engine receives the messages, it searches for
  the local consumers to dispatch the messages. If there are no
  consumers, a silence is written for each message received. The
  silence indicates that the target side is aware of the message
  being received. In addition to writing silence, it will also
  send an acknowledgment to the source messaging engine. Once
  the source messaging engine receives the acknowledgment, it
  will remove the message.
  However, it is observed that no acknowledgment is being sent
  to the source messaging engine. Because of this, the source
  messaging engine will not remove these messages and the
  messages pile up on its side.
  

Problem conclusion

• To fix the problem, an acknowledgment is sent from the target
  messaging engine to the source messaging engine after every 50
  consecutive silences. This gap of 50 silence messages is
  chosen because sending acknowledgment for every silence
  message may cause network overhead.
  
  If any local consumers come up any time, an acknowledgement is
  always sent during the message delivery. This is a specific
  scenario in which there are no local consumers on the target
  side for a long time which results in never acknowledging
  messages received.
  
  The fix for this APAR is currently targeted for inclusion in
  fix packs 7.0.0.27, 8.0.0.6 and 8.5.0.2. Please refer to the
  Recommended Updates page for delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

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

  WAS SIB & SIBWS

• Fixed component ID

  620800101

Applicable component levels

• R800 PSY

     UP