We are getting OOM error after two days of server uptime with no activity on server. Last error was yesterday at night, no users was at that time. Application is simple, portlets through EJB getting DB data and shows it to users. And couple of MDB for service integration.

Portal: liferay-portal-6.1.1-ce-ga2
JBoss: jboss-7.1.1

Eclipse MAT analys result:

The thread org.xnio.nio.WorkerThread @ 0x7805f2110 Remoting "app1" write-1 keeps local variables with total size 839 636 144 (50,68%) bytes.

The memory is accumulated in one instance of "java.util.TreeMap$Entry" loaded by "<system class loader>".

Keywords
java.util.TreeMap$Entry