Diagnosing a potential memory leak in the administrative server

Technote (FAQ)
Problem
This technote contains steps to determine if a java.lang.OutOfMemoryError in the WebSphere/AppServer/logs/ tracefile is due to a Java™ heap memory leak, or if it is due to the Java heap size not being large enough.
Solution
A java.lang.OutOfMemoryErrors in the tracefile could mean that there is a memory leak in the AdminServer Java Virtual Machine (JVM™) process. However, this error might indicate the configured heap for the AdminServer JVM is not large enough.

To increase the heap size of the AdminServer process, do the following.

  1. Create backup copy of WebSphere/AppServer/bin/admin.config.
  2. Edit the admin.config file.
  3. Find the line com.ibm.ejs.sm.util.process.Nanny.adminServerJvmArgs and change the heap size from -Xmx128m (128 MB) to -Xmx256m.
  4. If increasing the -Xmx parameter does not prevent the java.lang.OutOfMemoryError, enable -verbosegc for the AdminServer by adding -verbosegc to the com.ibm.ejs.sm.util.process.Nanny.adminServerJvmArgs.
  5. Stop and restart WebSphere AdminServer and attempt to recreate the problem.
  6. The verbosegc information is written to the WebSphere/AppServer/logs/tracefile file.
  7. Examine this information to determine if there is a memory leak in the AdminServer. This is the case if the amount of heap memory in use, as shown by the verboseGC output,is continually increasing.
  8. If there is a potential memory leak, use either the runhprof facility or the IBM® heapdump to examine the contents of the heap and determine what is leaking. For more information on how to enable the IBM heapdump, refer to the following technotes.
  9. Refer to MustGather: Readme First to locate instructions for capturing additional information.











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, Administrative Console (all non-scripting)
Operating system(s): Multi-Platform
Software version: 3.5, 4.0
Software edition: Edition Independent
Reference #: 1175544
IBM Group: Software Group
Modified date: 2004-07-29