I could run this ok on both NIO and AIO by adding blocking parameters on the perf-test. BTW: on this typical usecase, AIO will be way slower because of the TimedBuffer, but it should scale when you have many threads. (I know Tim knows this... Saying this for everybody else). But if you set journal-aio-flush-on-sync = true on the main configuration file, the Journal will not wait any timeouts and it will flush the same way NIO would when a commit arrives. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4234821#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...