PK68411: WorkLoad Management Stack Overflow in HTTPSession Scenario

Java SDK 1.5 SR8 Cumulative Fix for WebSphere Application Server
Java SDK 1.5 SR10 Cumulative Fix for WebSphere Application Server
6.1.0.31: Java SDK 1.5 SR11 FP1 Cumulative Fix for WebSphere Application Server
6.1.0.33: Java SDK 1.5 SR12 FP1 Cumulative Fix for WebSphere
6.1.0.29: Java SDK 1.5 SR11 Cumulative Fix for WebSphere Application Server
6.1.0.35: Java SDK 1.5 SR12 FP2 Cumulative Fix for WebSphere
6.1.0.37: Java SDK 1.5 SR12 FP3 Cumulative Fix for WebSphere
6.1.0.39: Java SDK 1.5 SR12 FP4 Cumulative Fix for WebSphere Application Server
6.1.0.41: Java SDK 1.5 SR12 FP5 Cumulative Fix for WebSphere Application Server
6.1.0.43: Java SDK 1.5 SR13 Cumulative Fix for WebSphere Application Server
6.1.0.45: Java SDK 1.5 SR14 Cumulative Fix for WebSphere Application Server
6.1.0.47: WebSphere Application Server V6.1 Fix Pack 47
6.1.0.47: Java SDK 1.5 SR16 Cumulative Fix for WebSphere Application Server

APAR status

• Closed as program error.

Error description

• The SystemOut.logs show a number of error messages; more
  signficantly, the servers in the core group become
  non-responsive.  This is due to an infinite loop that occurs.
  This loop eventually causes a java.lang.StackOverflowError to
  occur.
     This is the error message that is logged with the exception.
     These show a number of java.lang.StackOverflowErrors.
  [6/27/08 0:50:20:401 EDT] 00000024 UserCallbacks E   HMGR0142E:
  An error
  occurred in a component called back by the High Availability
  Manager.
  The exception is java.lang.StackOverflowError
   at java.util.HashMap.putAllForCreate(HashMap.java:647)
   at java.util.HashMap.<init>(HashMap.java:303)
   at com.ibm.ws.cluster.topography.KeyRepositoryImpl.
  getDescriptionKey(KeyRepositoryImpl.java:96)
   at com.ibm.ws.cluster.service.ClusterManagementImpl.
  defineAttribute(ClusterManagementImpl.java:603)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  buildPartitionTable(HttpSessClusterObserver.java:350)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  notify(HttpSessClusterObserver.java:212)
   at com.ibm.ws.cluster.service.ClusterServiceImpl.
  handleNotification(ClusterServiceImpl.java:467)
   at com.ibm.websphere.cluster.topography.DescriptionA.
  notifyListeners(DescriptionA.java:244)
   at com.ibm.ws.cluster.topography.IntrinsicDescriptionA.
  setExtrinsicData(IntrinsicDescriptionA.java:238)
   at com.ibm.ws.cluster.service.ClusterManagementImpl.
  defineAttribute(ClusterManagementImpl.java:611)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  buildPartitionTable(HttpSessClusterObserver.java:350)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  notify(HttpSessClusterObserver.java:212)
   at com.ibm.ws.cluster.service.ClusterServiceImpl.
  handleNotification(ClusterServiceImpl.java:467)
   at com.ibm.websphere.cluster.topography.DescriptionA.
  notifyListeners(DescriptionA.java:244)
   at com.ibm.ws.cluster.topography.IntrinsicDescriptionA.
  setExtrinsicData(IntrinsicDescriptionA.java:238)
   at com.ibm.ws.cluster.service.ClusterManagementImpl.
  defineAttribute(ClusterManagementImpl.java:611)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  buildPartitionTable(HttpSessClusterObserver.java:350)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  notify(HttpSessClusterObserver.java:212)
   at com.ibm.ws.cluster.service.ClusterServiceImpl.
  handleNotification(ClusterServiceImpl.java:467)
   at com.ibm.websphere.cluster.topography.DescriptionA.
  notifyListeners(DescriptionA.java:244)
  ...
  at com.ibm.ws.cluster.topography.IntrinsicDescriptionA.
  setExtrinsicData(IntrinsicDescriptionA.java:238)
   at com.ibm.ws.cluster.service.ClusterManagementImpl.
  defineAttribute(ClusterManagementImpl.java:611)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  buildPartitionTable(HttpSessClusterObserver.java:350)
   at com.ibm.ws.webcontainer.httpsession.httprouting.
  HttpSessClusterObserver.
  notify(HttpSessClusterObserver.java:212)
   at com.ibm.ws.cluster.service.ClusterServiceImpl.
  handleNotification(ClusterServiceImpl.java:467)
   at com.ibm.websphere.cluster.topography.DescriptionA.
  notifyListeners(DescriptionA.java:244)
   at com.ibm.ws.cluster.topography.ClusterDescriptionImpl.
  setMemento(ClusterDescriptionImpl.java:939)
   at com.ibm.ws.cluster.topography.DescriptionManagerA.update
  (DescriptionManagerA.java:428)
   at com.ibm.ws.cluster.propagation.bulletinboard.
  BBDescriptionManager.updated(BBDescriptionManager.java:312)
   at com.ibm.ws.hamanager.bboard.LocalBulletinBoardStateManager
  $BBoardUserCallback.doCallback
  (LocalBulletinBoardStateManager.java:1441)
   at com.ibm.ws.hamanager.impl.Worker.run(UserCallbacks.java:260)
   at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1469)
  .
  KEYWORDS: performance degradation high CPU 100% slowdown looping
  StackOverflowError
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  WebSphere Application Server V6.1 users     *
  *                  with HTTPSession replication enabled        *
  ****************************************************************
  * PROBLEM DESCRIPTION: StackOverflow thrown from HAManager     *
  *                      thread as a result of a WorkLoad        *
  *                      Management (WLM) code loop              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  There is a path in the WLM code in the HTTPSession scenario in
  which the defining of an attribute can cause a notification to
  be sent that in turn will cause an attribute to be defined.
  This infinite loop will lead to a stack overflow.
  
  The Stack overflow is thrown from the HAManager code, but is
  the result of the problem in the WLM code running on their
  threads.
  

Problem conclusion

• The WLM code was rewritten to remove the potential for the
  infinite loop in the HTTPSession scenario, and thus avoid the
  StackOverflow error.
  
  The fix for this APAR is currently targeted for inclusion in
  fix pack 6.1.0.21.  Please refer to the Recommended Updates
  page for delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  WEBS APP SERV N

• Fixed component ID

  5724H8800

Applicable component levels

• R61A PSY

     UP

• R61H PSY

     UP

• R61I PSY

     UP

• R61P PSY

     UP

• R61S PSY

     UP

• R61W PSY

     UP

• R61Z PSY

     UP