2 Replies Latest reply on Sep 19, 2003 4:56 PM by jcrosbie

    Gauge monitor hanging with notification listeners

    jcrosbie

      I have gauge monitor running in JBoss 3.2 that is monitoring another MBean resource I created. I have a remote client that is registering itself as a notification handler for that gauge monitor, so it will receive high and low threshold alerts. I notice that when a new notification handler is registered, the JMX server creates an MBean instance in the JMX domain to manage that connection.

      When the client shuts down, the MBean remains and doesn't appear to ever go away. What's worse is that the gauge monitor appears to "freeze" in two ways. First, the monitor doesn't appear to be running as the values it reports are not consistent with the attribute it is monitoring. This leads to the second problem where notifications are not sent to new clients that register for notifications.

      A workaround seems to be that when the client shuts down we deregister all notification handlers. The gauge monitor continues functioning and new clients can connect and receive events. But this only works in the case where shutdown is normal. What I would expect is that after some time the server determines that clients are no longer available and thus silently removes them from the notification list. Is there a setting for this? Has anyone ever seen this before?

      Thanks.

        • 1. Re: Gauge monitor hanging with notification listeners

          Can you post a threaddump so we can see where it is
          getting stuck.

          Regards,
          Adrian

          • 2. Re: Gauge monitor hanging with notification listeners
            jcrosbie

            Murphy appears to have stepped in as my colleague and I are having a difficult time reproducing this problem. I will provide a thread dump as soon as we can nail down a solid recreation scenario.

            Another thing we are seeing is that when I get a reference to the RemoteMBeanServer and use it to do things such as register notification handlers, it appears to start a thread that doesn't "daemonize" itself. When our Swing client is shutdown this thread is still running. Is there something we need to do to shut down this thread?

            Thanks for your help.