1 Reply Latest reply: May 7, 2013 9:17 AM by 832521 RSS

    Memory leak on cluster


      We have got a weblogic server installation deployed on six servers HP-UX. Our installation has 21 weblogic servers and we have got a big problem on one of the clusters; this cluster has got two servers that have to be restarted after working for several days because the heap memory consumption does not have limits. For that reason I did a memory dump using JCONSOLE and after analyzing it using the Eclipse Memory Analyzer; I could detect that the main leak suspect is: weblogic.servlet.internal.session.ReplicatedSessionData. I did this analysis several times and the main suspect has been the same class.

      Problem Suspect 1
      One instance of "weblogic.cluster.replication.ReplicationManager" loaded by "sun.misc.Launcher$AppClassLoader @ 0x9ffffffeca2bf030" occupies 120,817,128 (11.38%) bytes. The memory is accumulated in one instance of "weblogic.utils.collections.ConcurrentHashMap$Entry[]" loaded by "sun.misc.Launcher$AppClassLoader @ 0x9ffffffeca2bf030".

      Problem Suspect 2
      7,921 instances of "*weblogic.servlet.internal.session.ReplicatedSessionData", loaded by "sun.misc.Launcher$AppClassLoader @ 0x9ffffffeca2bf030" occupy 634,519,688 (59.77%) bytes*. These instances are referenced from one instance of "java.util.Hashtable$Entry[]", loaded by "<system class loader>"

      Problem Suspect 3
      67 instances of "weblogic.utils.classloaders.ChangeAwareClassLoader", loaded by "sun.misc.Launcher$AppClassLoader @ 0x9ffffffeca2bf030" occupy 107,663,504 (10.14%) bytes

      Cluster´s JVM configuration: We have two nodes
      -d64 -Xms3584m -Xmx3584m -XX:MaxPermSize=1024m -XX:+UseParNewGC

      This is the information about my product:
      Product: Oracle Weblogic Server
      Product Version: 10.3.1
      Operating System: HP-UX Itanium
      OS Version: 11.31
      S: HPUX 11.31
      Processpr: 64 bit Itanium
      JDK Type:
      Virtual Machine:
      Java HotSpot(TM) 64-Bit Server VM version jinteg:09.27.08-08:51 IA64W
      Vendor: Hewlett-Packard Company

      Best regards,
      Raúl Castillo Castillo

      Edited by: 829518 on 11/04/2013 07:55 AM
        • 1. Re: Memory leak on cluster

          The problem is caused by an application that has a wrong timeout configuration:


          For that reason, sessions never die; I changed this parameter and the problem was solved.

          Best regards,
          Raúl Castillo