2 Replies Latest reply: Nov 25, 2013 7:04 PM by Johannes Schmidt RSS

Out of Memory Error with ConcurrentReaderHashMap on Jboss 5.1.0

Anil Mathew Newbie



   We are running on JBoss 5.1 / JDK 1.6 on Linux servers. During very high load we are seeing Out of Memory Error and it seems like related to the JBoss remoting.


   We took a heap dump and the Memory Analyzer shows the below instance is taking 25% of the memory:


One instance of "org.jboss.mx.server.MBeanServerImpl" loaded by "org.jboss.classloader.spi.base.BaseClassLoader @ 0x415b2fc8" occupies 65,055,032 (24.64%) bytes. The memory is accumulated in one instance of "EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap$Entry[]" loaded by "org.jboss.bootstrap.NoAnnotationURLClassLoader @ 0x42f8ba78".


  The details which is pointing ot the JBoss remoting classes:


Class Name                                                                                                                                                Shallow Heap Retained Heap

  1. EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap$Entry[2048]  Shallow Heap => 8,208    Retained Heap => 45,693,888

   EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap   Shallow Heap => 56      Retained Heap => 45,761,640

      EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap$Entry Shallow Heap => 24                Retained Heap => 45,761,688

          EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap$Entry[64] Shallow Heap => 272                Retained Heap => 64,584,776

             EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap Shallow Heap => 56                Retained Heap => 64,621,408

                  org.jboss.mx.server.registry.BasicMBeanRegistry Shallow Heap =>  48      Retained Heap => 64,621,680

                      org.jboss.mx.server.MBeanServerImpl Shallow Heap => 24       Retained Heap => 65,055,032


                         java.lang.Thread @ 0x42135bb8 Signal Dispatcher Native Stack, Thread







  Any thoughts on this please?



Anil Mathew

  • 1. Re: Out of Memory Error with ConcurrentReaderHashMap on Jboss 5.1.0
    Ron Sigal Master

    Hi Anil,


    Sorry for the delay.  Are you still having this problem?


    I'm not really sure about what I'm looking at here; in particular, what is pointing at what?  A Remoting server will try to find an MBeanServer.  Is this dump saying that the MBeanServerImpl points to the BasicMBeanRegistry which points to the ConcurrentReaderHashMap?  In any case, it doesn't seem as if Remoting has a direct pointer to the ConcurrentReaderHashMap, right?


    Also, I'm not sure what to make about the presence of the PooledInvoker in the dump.  That's not part of Remoting, and I don't know how it would be related to a Remoting server. 


    Can you add any information that would help me make sense of the dump?




  • 2. Re: Out of Memory Error with ConcurrentReaderHashMap on Jboss 5.1.0
    Johannes Schmidt Newbie

    Hey Anil, did you ever come to a conclusion?

    Thanks in advance