[jboss-user] [JBoss Messaging] - What is the purpose of the Journal files?

I have a very simple program that has two classes, both generate JMS messages and both accept each others messages with onMessage() methods. If I delete all the files that are in my data/journal directory, after startup I find that the program by default generates 400Mgs of journal files (40 files 10Mgs each). These seem to be defined in the jbm-configuration.xml file at about lines 85 to 94, here is the snippit : <!-- 10 MB journal file size --> | <journal-file-size>10485760</journal-file-size> | | <journal-min-files>40</journal-min-files> | | <!-- Maximum simultaneous asynchronous writes accepted by the native layer. | (parameter ignored on NIO) | You can verify the max AIO on the OS level at /proc/sys/fs/aio_max_nr. (aio-nr will give you the current max-aio being used) | --> | <journal-max-aio>5000</journal-max-aio> | | | I a curious, is this really necessary (400 MGs minimum) and what is it used for? | | Regards, | | GMarsh View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4203435#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...