After running some code like the code below, get a memory snapshot from the JVM. Note that it still holds a MarshallerReaderContext instance as a member of the ReteooStatefulSession instance.

-- Marshall/unmarshall code

//kBase = KnowledgeBaseFactory.newKnowledgeBase(...);
//kBase.addKnowledgePackages(kps);
//session = kBase.newStatefulKnowledgeSession(config, null);

//Insert some facts

// Marshall a session
Marshaller marshaller = MarshallerFactory.newMarshaller(session.getKnowledgeBase());
marshaller.marshall(bOut, session);
bOut.close();

// Restart the jvm if you like

// session = new session

//Unmarshall the session
Marshaller marshaller = MarshallerFactory.newMarshaller(session.getKnowledgeBase());

marshaller.unmarshall(bIn, session);
bIn.close();