The
application team was complaining that they are seeing a lot of Out Of
Memory When they try to deploy the application more than 3 times.
Now
we Got the Heap Dump and checked the instances that were causing the
heap To Full.
I
found out that
"org.jboss.virtual.plugins.context.zip.zipentrycontext" are
being loaded and
causing
the memory to fill.
As
The references of
"org.jboss.virtual.plugins.context.zip.zipentrycontext" are
being loaded
highly
and are taking more space in heap.
The
reason for this is the VFS ( Virtaul File System) In Jboss. This
Uses the temp location in JBoss to cache copies of Deployment Units
as to speed up the performance of the
application
Server.This also causes
the
"org.jboss.virtual.plugins.context.zip.zipentrycontext" to
load in to memory.
Besides
that the default configuration for the VFS Cache repeatedly creates
the Context
Objects
and once it times out and these objects are ready for Finalization
the GC could not
finalize
these objects completely causing the heap To Grow faster
The
Element that effects this was to prevent the caching of all
deployment units and
cleaning
up the Context objects are in
/config/jboss/ewp/5.0/domains/<Server>/conf/bootstrap/vfs.xml
( One of the Core File
For
Changing the Virtual File Settings)
We
need to change the Element realCache from IterableTimedVFSCache to
TimedVFSCache.
<property
name="realCache">
<bean
class="org.jboss.virtual.plugins.cache.TimedVFSCache"/>
<!--
<bean
class="org.jboss.virtual.plugins.cache.IterableTimedVFSCache"/>
-->
</property>
Once
the Changes are done these Classes will not be loaded heavily .This
is solved in Jboss 5.1.0
Happy
learning :-)
