JBM 1.x will use something like 2 threads per session (I would have to check to be sure), so if you create a lot of sessions, you'll have a lot of threads. On later Linux kernels - this is rarely an issue - they can support very large numbers of lightweight threads. If you're clients are disconnecting without closing connections, then they're badly behaved clients - if you have access to change their code so they do close before exiting then I suggest you do that. Or perhaps the clients are crashing so there is little chance to do that. In any case JBM will detect such clients and clean up their resources, however this takes a while (maybe 30 seconds or a minute) depending on the ping settings. (That's the purging mechanism). View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4160925#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...