PH42333: TCP CONNECTIONS TO WEBSPHERE MQ LEAK WHEN USING JMS 2.0

APAR status

• Closed as program error.

Error description

• JMSContexts destroyed during the unused timeout reaping
  mechanism do not cleanup the underlying resources resulting in
  an exhaustion of MQ Connection Handles (HConns).
  

Local fix

• The issue can be worked around by setting the reaping mechanism
  to longer (or even disabling it) for the JMS Connection
  Factory's connection pool and presumably setting the Session
  pool's reap+unused time down to get the desired behaviour
  regarding clearing up older, unused JMSContexts.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:  WebSphere Application Server users of JMS   *
  *                  2.0                                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: The use of the reaping mechanism for    *
  *                      unused or aged timeouts with JMS 2.0    *
  *                      resulted in exhaustion of MQ            *
  *                      Connection Handles.                     *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The JMSContext.destroy method did not correctly invoke the
  J2C component to free the underlying connections.  JMSContexts
  are typically pooled and reused however they are also
  destroyed(while the underlying connection is still active)
  during the reaping mechanisms for unused and aged timeouts.
  When these reaping mechanisms were invoked, the underlying
  connections would remain active and would not be reused when
  new JMSContexts were created, leading to the exhaustion of
  underlying connections.
  

Problem conclusion

• The messaging component was modified so that the destruction
  of JMSContexts interacted correctly with the J2C component to
  free up the underlying connections.
  
  The fix for this APAR is targeted for inclusion in fix pack
  9.0.5.12. For more information, see 'Recommended Updates for
  WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

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

  WEBS APP SERV N

• Fixed component ID

  5724H8800

Applicable component levels