1 Reply Latest reply on Jun 13, 2005 7:57 AM by Soeren Gerlach

    Problem with finding the local cache group for a new member

    Soeren Gerlach Newbie

      We just started to test some of the JBossCache in our application but run into sort of problem several times. Currently I see hardly a pattern, but just a symptom, as from time to time new clients don't seem to find the local cache group right at the start.

      Following example: (log has been shortened a little for readability)

      ------------------------------------------------------------------------------------------------------------------------------------------------------------
      2005-06-13 08:44:04,209 [main] INFO org.jboss.cache.TreeCache - state could not be retrieved (must be first member in group)
      2005-06-13 08:44:04,225 [MessageDispatcher up processing thread] INFO org.jboss.cache.TreeCache - viewAccepted(): new members: [PC008229:3345]
      2005-06-13 08:44:04,225 [MessageDispatcher up processing thread] INFO org.jboss.cache.TreeCache - new cache is null (maybe first member in cluster)
      ------------------------------------------------------------------------------------------------------------------------------------------------------------

      Although some other clients are already up and running the last client starting thinks, it is the first member in the group. But 1:40 later at the same client following happens:

      ------------------------------------------------------------------------------------------------------------------------------------------------------------
      2005-06-13 08:45:44,505 [MessageDispatcher up processing thread] INFO org.jboss.cache.TreeCache - viewAccepted(): new members: [PC008229:3345, pc008234:4502, pc008602:3907]
      2005-06-13 08:45:44,505 [UpHandler (GMS)] ERROR org.jgroups.protocols.pbcast.GMS - [PC008229:3345] received view <= current view; discarding it (current vid: [PC008229:3345|2], new vid: [PC008229:3345|2])
      ------------------------------------------------------------------------------------------------------------------------------------------------------------

      Suddenly the other clients seem to become "visible" in any way. Quite obivously other clients and this client (PC008229) now have two different views of the cache, as it looks like they don't share their contents. This totelly matches with what we see in the application, some 8 clients behave like they have been split up randomly in 2-3 groups. Currently I have problems to reprocude this reliable as the problem sometimes pops up.


      Environment
      --------------
      * The network is multicast enabled, all PCs are connected with a switch on the same network.
      * JBossCache 1.2.2
      * Windows XP professional for all clients


      Thanks for any hints,
      Soeren Gerlach

        • 1. Re: Problem with finding the local cache group for a new mem
          Soeren Gerlach Newbie

          One addition: I just looked at some more client logs and found that another client joined the group later on. The client which logs I already posted now seems to "see" something more:

          2005-06-13 08:46:40,036 [MessageDispatcher up processing thread] INFO org.jboss.cache.TreeCache - viewAccepted(): new members: [PC008229:3345, pc008234:4502, pc008602:3907, pc008310:1276]
          2005-06-13 08:46:40,052 [MessageDispatcher up processing thread] INFO org.jboss.cache.TreeCache - locking the tree to obtain transient state
          2005-06-13 08:46:40,130 [MessageDispatcher up processing thread] INFO org.jboss.cache.TreeCache - returning the transient state (43492 bytes)


          But regarding from the logs it is unclear to me at what state the local cache now is.


          Regards,
          Soeren Gerlach