Looks like this could be "user error". In the above code, it looks like objects are getting added to cache locations "/i/j". While each objects is removed from "/i/j", the "/i" node remains (leaked by the user). I added an additional statement: cache.remove(fqn); That seems to clean it up, and the code can execute forever without leaking memory. However, I briefly tried doing this in JBossCache 2.0 (using attach()/detach() instead of putObject()/remove()), and it appears that the heap-usage still grows rapidly, even though it looks like all the cache nodes are getting removed. I think we'll be using 1.4, so I won't investigate it further. Thanks to those who took a look at this. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4110269#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...