title: Heap Dump Analysis needs your Attention
body: <p>I have a weblogic server that throws OOM error when it starts. Because of which my application is not behaving properly.</p>
  
  <p>I have collected Heap dump [Snap Shot below], however, I am not good at understanding the output.</p>
  
  <p><a href="http://img51.imageshack.us/img51/7470/heapanalysis.jpg" rel="nofollow noreferrer">Image Snap: http://img51.imageshack.us/img51/7470/heapanalysis.jpg</a></p>
  
  <p>Can you please help understand why am i getting the OOM errors ?
   Below are the JVM arguments.</p>
  
  <pre><code> Starting WLS with line:
   /java -server   -Xms1536m -Xmx1536m -XX:PermSize=512m -XX:MaxPermSize=512m -XX:NewSize=512m -XX:MaxNewSize=512m -XX:SurvivorRatio=6 -Xnoclassgc -XX:+DisableExplicitGC -verbose:gc -XX:+UseParNewGC -XX:+CMSParallelRemarkEnabled -XX:+UseConcMarkSweepGC -XX:+CMSClassUnloadingEnabled -XX:+CMSIncrementalMode -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+HeapDumpOnOutOfMemoryError   
  </code></pre>
  
  <p>Below is the errors seen in the logs.</p>
  
  <pre><code>&gt; java.lang.OutOfMemoryError: Java heap space Dumping heap to
  &gt; java_pid16660.hprof ...
  &gt; 115.814: [GC [1 CMS-initial-mark: 743854K(1048576K)] 743854K(1507328K), 0.0050472 secs]
  &gt; 115.819: [CMS-concurrent-mark-start] Heap dump file created [778142756 bytes in 3.935 secs] &lt;Jan 20, 2013 10:56:05 PM PST&gt; &lt;Critical&gt;
  &gt; &lt;WorkManager&gt; &lt;BEA-002911&gt; &lt;WorkManager weblogic.kernel.System failed
  &gt; to schedule a request due to java.lang.OutOfMemoryError: Java heap 
  &gt; space java.lang.OutOfMemoryError: Java heap space
  &gt; &gt; &lt;Jan 20, 2013 10:56:05 PM PST&gt; &lt;Critical&gt; &lt;WorkManager&gt; &lt;BEA-002911&gt; &lt;WorkManager weblogic.kernel.System failed to schedule a request due
  &gt; to java.lang.ArrayIndexOutOfBoundsExcept ion: 26214404
  &gt; java.lang.ArrayIndexOutOfBoundsException: 26214404
  &gt;         at weblogic.work.CalendarQueue.add(CalendarQueue.java:39)
  &gt;         at weblogic.work.RequestManager.addToPriorityQueue(RequestManager.java:263)
  &gt;         at weblogic.work.RequestManager.executeIt(RequestManager.java:235)
  &gt;         at weblogic.work.ServerWorkManagerImpl.schedule(ServerWorkManagerImpl.java:142)
  &gt;         at weblogic.corba.cos.transactions.RecoveryRegistrar.run(RecoveryRegistrar.java:47)
  &gt;         Truncated. see log file for complete stacktrace
  </code></pre>