[jboss-dev] Multiple classLoaders for a single WAR file on Tomcat

[Clebert Suconic]

This is probably a question for Remy:

Why Tomcat creates multiple ClassLoaders for every deployment?

Is this by design or this is a leak?

For a single WAR, I'm seeing 4 classLoaders deployed just wasting 
PermGeneration memory.

For example, I deployed a single WAR, and I've got this Servlet loaded 
by 4 distinct classLoaders. and this is a standard behavior I have seen 
on Tomcat for a long time already.

org.jboss.on.plugins.servlet.test.Counter:

- java.net.URLClassLoader at 10891966
- org.jboss.web.tomcat.tc5.WebAppClassLoader at 18775238
- java.net.URLClassLoader at 22498184
- org.jboss.web.tomcat.tc5.WebAppClassLoader at 8238932


Also... if you use any other profiler (besides the ClassLoader analysis 
I've written on JBossProfiler) you could be foolished by them as those 
classes won't have any instances... Just the classDef loaded on the heap.



Clebert