The eviction event queue holds event objects that describe reads and writes to the cache. Those are used by the eviction handling code to determine which nodes to evict (e.g. what nodes are LRU). The queue itself takes memory, but it's a bounded queue so it won't grow beyond 200,000 entries. But these WARN messages are a sign that eviction is overloaded, which can result in excess nodes being left in the cache. I would reduce your wakeUpIntervalSeconds to 1. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4224132#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...