We have been facing Out of Memory errors in our App server for sometime. We see the used heap size increasing gradually until finally it reaches the available heap in size. This happens every 3 weeks after which a server restart is needed to fix this.
Upon analysis of the heap dumps we find the problem to be objects used in JSPs.
Can JSP objects be the real cause of Appserver memory issues? How do we free up JSP objects (Objects which are being instantiated using usebean or other tags)?
We have a clustered Websphere appserver with 2 nodes and an IHS.
EDIT: The findings above are based on the heap-dump and nativestderr log analysis given below using the IBM support assistant
nativestd err log analysis:
alt text http://saregos.com/wp-content/uploads/2010/03/chart.jpg
Heap dump analysis:
![alt text][2]
Heap dump analysis showing the immediate dominators (2 levels up of hastable entry in the image above)
![alt text][3]
The last image shows that the immediate dominators are in fact objects being used in JSPs.
EDIT2: More info available at http://saregos.com/?p=43
Triggering the garbage collection manually doesn’t solve your problem – it won’t free resources that are still in use.
You should use a profiling tool (like jProfiler) to find your leaks. You problably use code that stores references in lists or maps that are not released during runtime – propably static references.