WebLogic 10.3.3 Admin server OutOfMemoryError: PermGen

 

WebLogic 10.3.3 Admin server OutOfMemoryError: PermGen

Here I am going to discuss about the case that describes the analysis to resolution of a memory leak (PermGen space) problem experienced for the admin server with a Weblogic 10.3.3 environment using Sun JDK 1.6.0_21.
The permanent generation (PermGen) is special because it holds meta-data describing user classes (classes that are not part of the Java language). Examples of such meta-data are objects describing classes and methods and they are stored in the Permanent Generation. Applications with large code-base can quickly fill up this segment of the heap which will cause java.lang.OutOfMemoryError: PermGen no matter how high your -Xmx and how much memory you have on the machine.

Environment specifications

Java EE server: Weblogic 10.3.3
Operating Environment: Solaris 10
JDK: Sun JDK 1.6.0_21  VM arguments for Perm Space are given as below:
-XX:PermSize=48m -XX:MaxPermSize=128m -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+HeapDumpOnOutOfMemoryError
This problem was becoming unmanageable for the team to support in the production environment as admin server was constantly failing with this OutOfMemoryError.  We were worked with Oracle support team to fix this issue. The problem mitigation did involve restarting the admin server every day 2 times.

Analysis Factors

•       Recent change of the affected platform? No
•       Any recent traffic increase to the affected platform? No
•       Since how long this problem has been observed?  When it was migrated from WebLogic 9.2 to WebLogic 10.3.3
•       Is the permanent generation space growing suddenly or over time? It was observed using GC tool that the PermGen space is growing on a regular / daily basis.
•       Did a restart of the WebLogic server resolve the problem? No, restarting the WebLogic server is only used as a mitigation strategy to prevent the OutOfMemoryError.