4 Replies Latest reply on Sep 30, 2005 3:16 PM by Robert Costanzo

    Too many threads being marked as busy in JBoss

    Robert Costanzo Newbie

      I am noticing some strange behavior with my JBoss 3.2.6 cluster of 5 instances using apache and mod-jk 1.2.14 over AJP13 to connect. Even when there is virtually no load on the system, the currentThreadsBusy count in the jk-8009 ThreadPool MBean shows a relatively high number.

      For example, if I look at a single point in time, my apaches are processing 40 requests each (including static content which doesn't get passed on to JBoss), and the JBoss instances are reporting 225 threads busy. This seems like impossible math to me since I don't see how apache forwarding say at most 10 requests to JBoss causes 225 threads to become busy.

      The only thing I can think of is that the threads aren't truly busy. When I ran a small load on a test instance and let it finish, I saw 21 threads busy afterwards. I waited hours, and it still said 21 threads busy. I then restarted apache (NOT JBoss), and it dropped to 1 thread busy.

      Is there a known issue with the mod-jk plugin and it making JBoss think its threads are busy when they really aren't? This becomes a major issue for me in production under high loads where I hit my maximum threads very quickly, but the box is under almost no load.

      Any help would be greatly appreciated.

      -Rob