PM31699: CCL LEAKS AND OOME CAUSED BY NOTIFICATIONSERVICEDISPATCHER OR LOCALNOTIFICATIONSERVICEDISPATCHER THREAD LEAK

6.1.0.47: WebSphere Application Server V6.1 Fix Pack 47
6.1.0.39: Java SDK 1.5 SR12 FP4 Cumulative Fix for WebSphere Application Server
6.1.0.41: Java SDK 1.5 SR12 FP5 Cumulative Fix for WebSphere Application Server
6.1.0.43: Java SDK 1.5 SR13 Cumulative Fix for WebSphere Application Server
6.1.0.45: Java SDK 1.5 SR14 Cumulative Fix for WebSphere Application Server
6.1.0.47: Java SDK 1.5 SR16 Cumulative Fix for WebSphere Application Server
Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• After repeated redeployment of applications, native memory
  exhausted and java/lang/OutOfMemoryError was raised by Java.
  The OOM was caused by WebSphere CompoundClassLoader leaks. The
  CCL leaks were caused by NotificationServiceDispatcher thread or
  LocalNotificationServiceDispatcher thread referencing it's CCL
  by the contextClassLoader field.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server V6.1.0. It applies to all            *
  *                  platforms.                                  *
  ****************************************************************
  * PROBLEM DESCRIPTION: After repeated redeployment of          *
  *                      applications, native memory             *
  *                      exhausted and                           *
  *                      java/lang/OutOfMemoryError was raised   *
  *                      by Java.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  After repeated redeployment of applications, native memory
  exhausted and java/lang/OutOfMemoryError was raised by Java.
  The OOM was caused by WebSphere CompoundClassLoader leaks. The
  CCL leaks were caused by NotificationServiceDispatcher thread or
  LocalNotificationServiceDispatcher thread referencing it's CCL
  by the contextClassLoader field.
  

Problem conclusion

• The solution to the above-mentioned issue is for the
  NotificationDispatcher class to explicitly set the classloader
  to ExtClassLoader whenever a new thread is started on it.
  Since it no longer holds the CCL reference, it does not prevent
  the latter from being garbage collected during repeated
  redployment.
  
  APAR PM31699 is currently targeted for inclusion in Service
  Level (Fix Pack) 6.1.0.39 of WebSphere Application Server
  V6.1. There's no tracks for other releases since this fix is
  v6.1 specific.
  
  Please refer to URL:
  //www.ibm.com/support/docview.wss?rs=404&uid=swg27006970
  for Fix Pack availability.
  

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

  WEBSPHERE FOR Z

• Fixed component ID

  5655I3500

Applicable component levels

• R610 PSY UK69361

     UP11/07/16 P F107

Fix is available

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