JBoss stops flushing bean caches

[hw]

We are using JBoss 3.2.5 with Java 1.4.2_07. After some hours running JBoss, something is going completely wrong. We have written some little tools to monitor the amount of cached instances per bean over time. From starting jboss on evening until next noon, everything is normal, amount of caches increased and decreased. But around noon after jboss-start, this correct behavior disappeared. Every bean cache increased up to his limit, some beans faster, some slower, depending on how often the bean was used. But no cache decreased, jboss consumed more and more memory. The rest of day until night, all caches still grew. Even in night with nearly no traffic, the caches doesn't decrease, they keep there level, and that is different to the first night after starting jboss on evening.

Flushing the caches manually with jmx-console is possible, but it is not really a solution, I think. Does anyone notice such behavior? Is there a way to monitor the cache activity itselfs, maybe like monitoring the gc (when, why etc.)?

We have not modified the bean cache strategy, only the cache size is reduced to 1000. The beans are Entity Beans with CMP and some
stateless/statefull SessionBeans.

[hw]

Here is a little graphic to visualize the problem. It's just the graph of some bean caches over time, using the output of jmx-console. You can see the change of flushing caches on noon.

http://img204.exs.cx/img204/2800/caches6fy.png

[starksm64]

If you have a testcase to reproduce the problem open a bug in our jira (http://jira.jboss.com). Enable trace level logging on the org.jboss.ejb category to get more info about the server behavior.

 <category name="org.jboss.mx.loading">
 <priority value="TRACE" class="org.jboss.logging.XLevel"/>
 </category>