We have one Java Virtual machine(appserver) which connects to the database and perform work.This JVM spawns 20 threads to the database to do its work.Now,the real problem is all the 20 threads are being used up and JVM is unable to spawn a new thread and the application is struck and eventually not responding and our website is down.In the database ,when this incident occurs,I am seeing only one or two applications in 'UOW Executing' status.Any idea,what's going on here?

The problem is at the JVM side. Either it is not sharing the connections properly or the users of the connections are not behaving properly.

Andy

Any tests I can perform to rule out DB2 database as culprit?

On the DB2 server, try to connect to the database. If it works then DB2 is not the problem.

Andy

Thankyou...but the issue doesn't occur everytime...it connects to the db well and continues its work for 10 to 12 hrs and then suddenly the hang occurs..I am able to connect ,run sql's take snapshots etc when this issue happens..so you say its not db2.Any idea if db2 server(lpar) not the database may be cuasing this?

If you are able to use the database outside the application while the application is hanged, then it is not the database.

Andy

thankyou..I think that answers my question..appreciate it

My guess would be that you probably have a deadlock in your application. It takes some time until the conditions are meat, i.e. the right code is running concurrently in multiple threads to run into the deadlock. That would at least explain the 10-12h.