anonymous wrote : BTW, I also have to increase default max AIO to 1000, since it was intermittently failing on my box due to run out of AIO. | You run out of AIO when you have more than MAX_AIO_SIZE * NumberOfFiles > 64k (The max-aio configured at OS level). so.. increasing the default MAX_AIO_SIZE will get you to have a lower number of files.. not the opposite. When you have more writes than max-aio, they will just wait on the executor until the queue is freed up. So I don't think that would be your case. BTW: Better thinking now.. I think I should rename that parameter to something else such as AIO_QUEUE_SIZE. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4237443#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...