Thank you for your reply. Those are our customer's servers, so I don't have a direct line to JBoss customer support, but I might try to have a ticket opened once I have something more concrete. I am planning on getting a heap dump when I get the chance to reproduce this, but I was wondering how this is tied to clustering. I did some simple tests, and it does not seem (at least from the org.jboss.cache logs) that any replication happens while n1 is being shut down. But still something is triggering increased memory usage on n2 at exactly this point. Is there any other log category that might give more insight into what is happening? View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4258197#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...