Jakub, Processinstances that are 'running' should not be compared to running threads in Java. If they are 'running' but only have tasks that have to be acted upon but are currently not, are just in the database. So millions of 'running' instances are no problem if your database can handle it. If you mean really concurrent processes that are loaded into memory and acted upon, I have no idea. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4164571#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...