PI76509: Hang on org/apache/webbeans/context/sessioncontext.addchildrequest

PI76509:Hang on org/apache/webbeans/context/sessioncontext.addchildrequest
8.5.5.12: WebSphere Application Server V8.5.5 Fix Pack 12
8.0.0.14: WebSphere Application Server V8.0 Fix Pack 14
8.5.5.13: WebSphere Application Server V8.5.5 Fix Pack 13
8.0.0.15: WebSphere Application Server V8.0 Fix Pack 15
8.5.5.14: WebSphere Application Server V8.5.5 Fix Pack 14
8.5.5.15: WebSphere Application Server V8.5.5 Fix Pack 15
8.5.5.17: WebSphere Application Server V8.5.5 Fix Pack 17
8.5.5.20: WebSphere Application Server V8.5.5.20
8.5.5.18: WebSphere Application Server V8.5.5 Fix Pack 18
8.5.5.19: WebSphere Application Server V8.5.5 Fix Pack 19
8.5.5.16: WebSphere Application Server V8.5.5 Fix Pack 16
8.5.5.21: WebSphere Application Server V8.5.5.21

APAR status

• Closed as program error.

Error description

• Hanging threads after applying fix pack 8.5.5.11 or liberty
  16.0.0.4 or 17.0.0.1
  
  SystemOut.log and Java cores show:
  
  [9-2-17 16:13:45:421 CET] 0000002f ThreadMonitor W   WSVR0605W:
  Thread "WebContainer : 35" (0000011d) has been active for 697463
  milliseconds and may be hung.  There is/are 1 thread(s) in
  total in the server that may be hung.
  at
  java/util/HashMap.put(HashMap.java:506(Compiled
  Code)) at java/util/HashSet.add(HashSet.java:229(Compiled Code))
  at
  org/apache/webbeans/context/SessionContext.addChildRequest(Sessi
  onContext.java:118(Compiled Code))
  at
  org/apache/webbeans/web/context/WebContextsService.initRequestCo
  ntext(WebContextsService.java:550(Compiled Code))
  at
  org/apache/webbeans/web/context/WebContextsService.startContext(
  WebContextsService.java:417(Compiled Code))
  at
  com/ibm/ws/webbeans/services/JCDIWebListener.requestInitialized(
  JCDIWebListener.java:321(Compiled Code))
  at
  com/ibm/ws/webcontainer/webapp/WebApp.notifyServletRequestCreate
  d(WebApp.java:1908(Compiled Code))
  
  Additional symptoms: session invalidation threads begin to
  become blocked and an error similar to the following is logged
  in javacores
  
  Webcontainers 38,23,20,18 and 7 were blocked behind webcontainer
  21 which was runnable and Owns Monitor Lock on
  com/ibm/ws/session/store/memory/MemorySession@0x000000000852C740
  
  at
  java/util/HashMap$HashIterator.remove(HashMap.java:955(Compiled
  Code))
  at
  org/apache/webbeans/context/SessionContext.isAnyRequestActive(Se
  ssionContext.java:137(Compiled Code))
  at
  org/apache/webbeans/context/SessionContext.isAnyRequestActive(Se
  ssionContext.java:123(Compiled Code))
  at
  org/apache/webbeans/web/context/WebContextsService.destroySessio
  nContext(WebContextsService.java:717(Compiled Code))
  at
  org/apache/webbeans/web/context/WebContextsService.endContext(We
  bContextsService.java:269(Compiled Code))
  at
  com/ibm/ws/webbeans/services/JCDIWebListener.sessionDestroyed(JC
  DIWebListener.java:397(Compiled Code))
  at
  com/ibm/ws/session/http/HttpSessionObserver.sessionDestroyed(Htt
  pSessionObserver.java:180(Compiled Code))
  at
  com/ibm/ws/session/SessionEventDispatcher.sessionDestroyed(Sessi
  onEventDispatcher.java:160(Compiled Code))
  at
  com/ibm/ws/session/StoreCallback.sessionInvalidated(StoreCallbac
  k.java:126(Compiled Code))
  at
  com/ibm/ws/session/store/memory/MemorySession.invalidate(MemoryS
  ession.java:232)
  at
  com/ibm/ws/session/store/memory/MemorySession.invalidate(MemoryS
  ession.java:878)
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server                                      *
  ****************************************************************
  * PROBLEM DESCRIPTION: Concurrent modification can corrupt a   *
  *                      HashSet leading to hanging threads      *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A HashSet in the org.apache.webbeans.context.SessionContext
  was undergoing concurrent modification. A hanging
  thread with SessionContext on the stack is likely to be
  resolved by this APAR.
  

Problem conclusion

• The Set in question was updated to use a different Set
  implementation that can accept concurrent modification.
  
  The fix for this APAR is currently targeted for inclusion in
  fix packs 8.5.5.12, 8.0.0.14 and Liberty 17.0.0.2.  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

• R800 PSY

     UP

• R850 PSY

     UP

• R900 PSY

     UP