It's not bad. It's used for a lot of open source apps. But it lacks all of the transaction features of Sleepycat. I recommend you use it with ASYNC on if possible. One thing I've seen is that JBoss Cache sort of has a goofy implementation of put() where all the data has to be loaded from the cache loader before it's replaced. So do a remove() then put() if possible. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4191452#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...