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PM45446: DEADLOCK THREADS DURING INVALIDATION WITH SESSION TRACING ENABLED.

Fixes are available

8.0.0.3: WebSphere Application Server V8.0 Fix Pack 3
7.0.0.23: WebSphere Application Server V7.0 Fix Pack 23
8.0.0.4: WebSphere Application Server V8.0 Fix Pack 4
7.0.0.25: WebSphere Application Server V7.0 Fix Pack 25
8.0.0.5: WebSphere Application Server V8.0 Fix Pack 5
7.0.0.27: WebSphere Application Server V7.0 Fix Pack 27
8.0.0.6: WebSphere Application Server V8.0 Fix Pack 6
7.0.0.29: WebSphere Application Server V7.0 Fix Pack 29
8.0.0.7: WebSphere Application Server V8.0 Fix Pack 7
8.0.0.8: WebSphere Application Server V8.0 Fix Pack 8
7.0.0.31: WebSphere Application Server V7.0 Fix Pack 31
7.0.0.27: Java SDK 1.6 SR13 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.33: WebSphere Application Server V7.0 Fix Pack 33
8.0.0.9: WebSphere Application Server V8.0 Fix Pack 9
7.0.0.35: WebSphere Application Server V7.0 Fix Pack 35
8.0.0.10: WebSphere Application Server V8.0 Fix Pack 10
7.0.0.37: WebSphere Application Server V7.0 Fix Pack 37
8.0.0.11: WebSphere Application Server V8.0 Fix Pack 11
7.0.0.39: WebSphere Application Server V7.0 Fix Pack 39
8.0.0.12: WebSphere Application Server V8.0 Fix Pack 12
7.0.0.41: WebSphere Application Server V7.0 Fix Pack 41
8.0.0.13: WebSphere Application Server V8.0 Fix Pack 13
7.0.0.43: WebSphere Application Server V7.0 Fix Pack 43
8.0.0.14: WebSphere Application Server V8.0 Fix Pack 14
7.0.0.45: WebSphere Application Server V7.0 Fix Pack 45
8.0.0.15: WebSphere Application Server V8.0 Fix Pack 15
7.0.0.23: Java SDK 1.6 SR10 FP1 Cumulative Fix for WebSphere
7.0.0.25: Java SDK 1.6 SR11 Cumulative Fix for WebSphere Application Server
7.0.0.27: Java SDK 1.6 SR12 Cumulative Fix for WebSphere Application Server
7.0.0.29: Java SDK 1.6 SR13 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.45: Java SDK 1.6 SR16 FP60 Cumulative Fix for WebSphere Application Server
7.0.0.31: Java SDK 1.6 SR15 Cumulative Fix for WebSphere Application Server
7.0.0.35: Java SDK 1.6 SR16 FP1 Cumulative Fix for WebSphere Application Server
7.0.0.37: Java SDK 1.6 SR16 FP3 Cumulative Fix for WebSphere Application Server
7.0.0.39: Java SDK 1.6 SR16 FP7 Cumulative Fix for WebSphere Application Server
7.0.0.41: Java SDK 1.6 SR16 FP20 Cumulative Fix for WebSphere Application Server
7.0.0.43: Java SDK 1.6 SR16 FP41 Cumulative Fix for WebSphere Application Server

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APAR status

  • Closed as program error.

Error description

  • DEADLOCK THREADS DURING INVALIDATION WITH SESSION TRACING
    ENABLED:
    
    Websphere Application Server V7.0.0.17
    Distributed operating systems.
    
    With session tracing active, customers may experience a deadlock
    in threads during invalidation.  The deadlocked threads will be:
    
    
    com/ibm/ws/session/store/common/BackedHashMap.superRemove(Backed
    java:559(Compiled Code))
    com/ibm/ws/session/store/mtm/MTMHashMap.superRemove(MTMHashMap.j
    ava:584
    com/ibm/ws/session/store/mtm/MTMHashMap.removePersistedSession(M
    TMHashMa
    com/ibm/ws/session/store/common/BackedStore.removeSession(Backed
    Store.java:118)
    com/ibm/ws/session/store/memory/MemorySession.invalidate(MemoryS
    ession.java:225)
    com/ibm/ws/session/store/common/BackedSession.invalidate(BackedS
    ession.java
    
    and
    
    java/lang/String.valueOf(String.java:1512(Compiled Code))
    java/lang/StringBuffer.append(StringBuffer.java:187(Compiled
    Code))
    com/ibm/ws/session/utils/LRUHashMap$CacheEntryWrapper.toString(L
    RUHashMap.java:427(Compiled Code))
    java/lang/String.valueOf(String.java:1512(Compiled Code))
    com/ibm/ws/session/utils/LRUHashMap.removeGuts(LRUHashMap.java:2
    58(Compiled Code))
    com/ibm/ws/session/utils/LRUHashMap.remove(LRUHashMap.java:241(C
    ompiled Code))
    com/ibm/ws/session/store/common/BackedHashMap.superRemove(Backed
    HashMap.java:559(Compiled Code))
    com/ibm/ws/session/store/mtm/MTMHashMap.superRemove(MTMHashMap.j
    ava:584(Compiled Code))
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  IBM WebSphere Application Server Version 7  *
    *                  and 8 users of session persistence with     *
    *                  session tracing enabled.                    *
    ****************************************************************
    * PROBLEM DESCRIPTION: When session tracing is enabled and     *
    *                      database or memory to memory            *
    *                      persistence is enabled, a deadlock      *
    *                      may occur during invalidation.          *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    When session tracing is enabled and the maximum in memory
    session count has been exceeded a deadlock can occur if the
    session is being removed from the in memory table at the same
    time as invalidation.
    

Problem conclusion

  • The trace statement which caused the deadlock was modified to
    print a smaller amount of session information.
    This prevents the trace statement from causing deadlock.
    
    The fix for this APAR is currently targeted for inclusion in
    fix packs 7.0.0.23 and 8.0.0.3 . 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 number

    PM45446

  • Reported component name

    WEBS APP SERV N

  • Reported component ID

    5724H8800

  • Reported release

    700

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-08-10

  • Closed date

    2011-12-13

  • Last modified date

    2011-12-13

  • 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

  • R700 PSY

       UP

  • R800 PSY

       UP



Document information

More support for: WebSphere Application Server
General

Software version: 7.0

Reference #: PM45446

Modified date: 13 December 2011