IV18624: JAVA/JMS APPLICATION LEAKS CONNECTIONS WHEN ATTEMPTING TO PUT MESSAGE WITH AUTOMATIC CLIENT RECONNECTION ENABLED.

WebSphere MQ V7.0 Fix Pack 7.0.1.9

APAR status

• Closed as program error.

Error description

• Applications using the WebSphere MQ classes for Java
  Version 7.0.1.8 repeatedly reconnect and finally consume all
  the available connections of the queue manager.
  
  Traces show repeated occurrences of completion code "2" and
  reason code "2009", and internal exceptions are traced out
  containing the following callstack:
  
  Throwing Exception: com.ibm.mq.jmqi.JmqiException: CC=2;RC=2009
  com.ibm.mq.jmqi.remote.internal.RemoteHconn.getConnection
  (RemoteHconn.java:855)
  com.ibm.mq.jmqi.remote.internal.RemoteHconn.isSPISupported
  (RemoteHconn.java:3608)
  com.ibm.mq.jmqi.remote.internal.RemoteFAP.jmqiPutMessageWithProp
  s(RemoteFAP.java:7495)
  
  At the queue manager, the number of instances of the channel
  used by the Java application are observed to continually
  increase. The number of open output handles on the queue the
  application is attempting to put messages to also increases.
  These increases will continue until either: the application is
  terminated, the maximum number of open output handles for the
  queue is reached, or the maximum number of channel instances is
  reached.
  

Local fix

• Disable automatic client reconnection by removing
  the stanza "DefRecon=YES" from the client configuration file
  (mqclient.ini).
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of the WebSphere MQ V7.0.1.8 classes
  for JMS who have enabled automatic client reconnection for
  either the specific connection in use or the entire Java
  Virtual Machine (JVM).
  
  This issue also affects users of the WebSphere MQ V7.0.1.8
  classes for Java where applications are running inside a JVM
  where Automatic Client Reconnection has been enabled for the
  entire JVM.
  
  Platforms affected:
  All Distributed (iSeries, all Unix and Windows) +Java +Java zOS
  ****************************************************************
  PROBLEM SUMMARY:
  APAR IC79103 added additional checks to determine if particular
  internal API calls are available on a queue manager during an
  MQPUT operation.
  
  In the case where Automatic Client Reconnection is enabled,
  there may be multiple objects in the JVM representing
  connections to the queue manager. In this case, the checks
  added by APAR IC79103 were made on the wrong object, causing an
  unexpected value to be returned. The WebSphere MQ client
  interpreted this unexpected value to mean there was a problem
  with the connection and triggered the reconnection logic,
  creating a new connection to the queue manager. As a
  consequence of the check being performed on the wrong object,
  the correct object was not cleaned up by the reconnection
  object, causing the underlying connection to leak.
  

Problem conclusion

• The WebSphere MQ classes for Java and classes for JMS have been
  updated so that the check for support for internal API calls is
  made on the correct object when Automatic Client Reconnection
  is enabled.
  
  
  
  | MDVREGR 7.0.1-WS-MQ-AixPPC64-FP0008       |
  | MDVREGR 7.0.1-WS-MQ-HpuxIA64-FP0008       |
  | MDVREGR 7.0.1-WS-MQ-HpuxPaRISC64-FP0008   |
  | MDVREGR 7.0.1-WS-MQ-LinuxIA32-FP0008      |
  | MDVREGR 7.0.1-WS-MQ-LinuxPPC64-FP0008     |
  | MDVREGR 7.0.1-WS-MQ-LinuxS390X-FP0008     |
  | MDVREGR 7.0.1-WS-MQ-LinuxX64-FP0008       |
  | MDVREGR 7.0.1-WS-MQ-SolarisSparc64-FP0008 |
  | MDVREGR 7.0.1-WS-MQ-SolarisX64-FP0008     |
  | MDVREGR 7.0.1-WS-MQ-Windows-FP0008        |
  
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v7.0       7.0.1.9
  
  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