"gothemilan" wrote : Hi Friend, | | May be this information could help us to find the solutions. we only have 100 Max connection pool in this file defined, should we increase this coz as i already said before, we have more than 250 users at a time(concurrent). | This attribute is for Web server threads (check localhost:8080/ and click status how many threads are busy) I think you can also check max used threads on JMX console. You have exception from "org.jboss.resource.adapter.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:73)" so you probably you don't close jdbc connection. Are you using finally block to close connections ? "jakiran" wrote : Also, you can access the jmx-console at http://localhost:8080/jmx-console and you will find a MBean named "name=MerliaDS,service=ManagedConnectionPool" under the jboss.jca section. Click on that link which will lead you to a page which shows the various attributes of the connection pool. One of them is the InUseConnectionCount. Check out the value of this. Also there is method listConnectionInUse on that JMX bean which show you which your code doesn't release connections. It is amazing JBoss feature which I used many times on production ;> View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4174762#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...