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PM97286: MEMORY LEAKING IN WEBSPHERE APPLICATION SERVER DEFAULT MESSAGING WHEN REMOTE GET IS USED IN PUBLISH/SUBSCRIBE.

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APAR status

  • Closed as program error.

Error description

  • The AnycastInputHandler$ReachabilityChangeListener is the one
    that is leaking as observed from the heapdumps.
    
    From the traces taken from [11/9/2013 10:45:59:164 EEST] to
    [11/9/2013 11:04:58:917 EEST], we observe that there are only
    three AnycastInputHandlers that get created and from the
    traces we also observe that these objects are being deleted.
    
    In the heapdump from before the traces, we observe that there
    are 51,209 objects of
    "com/ibm/ws/sib/processor/impl/AnycastInputHandler$ReachabilityC
    hangeListener" and the heapdump after the traces, we observe
    that there are 51,212 objects of
    "com/ibm/ws/sib/processor/impl/AnycastInputHandler$ReachabilityC
    hangeListener".
    
    The additional 3 objects were created during the time the
    traces were being captured as we observed.
    
    * Analyzing the code further, we observe that the
    ReachabilityChangeListener objects are not being cleared in
    certain code paths and since ReachabilityChangeListener is a
    subclass of AnycastInputHandler, even these objects are not
    being removed from the heap.
    
    Memory leaking in WAS Defualt Messaging when remote get is used
    in Publish/Subscribe.
    Accumulation of AnycastInputHandler$ReachabilityChangeListener
    objects in memory due to subscribers frequently connecting and
    disconnecting leading to memory leak.
    

Local fix

  • ..
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  Users of the default messaging provider for *
    *                  IBM WebSphere Application Server V8.5       *
    ****************************************************************
    * PROBLEM DESCRIPTION: Memory leak observed when using remote  *
    *                      get in Service Integration Bus where in *
    *                      majority of the heap was occupied with  *
    *                      "com/ibm/ws/sib/processor/impl/AnycastI *
    *                      nputHanlder$ReachabilityChangeListener" *
    *                      objects.                                *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    While using Service Integration Bus of WebSphere Application
    Server, memory leak was observed when using remote get and
    majority of the heap was occupied with the
    "com/ibm/ws/sib/processor/impl/AnycastInputHanlder$ReachabilityC
    hangeListener" objects.
    This problem is observed in the following scenarios -
    a) whenever a consumer tries to consume messages from a remote
    messaging engine where the subscription is present and the
    durable subscription home is on a different server,
    particularly when the durable subscriber frequently connects
    and disconnects
    b) when there are many durable subscribers getting created and
    connecting to the remote messaging engine where the durable
    subscription home does not exist.
    

Problem conclusion

  • The code has been modified to ensure that the objects
    "com/ibm/ws/sib/processor/impl/AnycastInputHanlder$ReachabilityC
    hangeListener" are removed correctly from all possible code
    paths whenever the durable subscriber disconnects and hence
    ensuring that there is no memory leak.
    
    The fix for this APAR is currently targeted for inclusion in
    fix pack 8.5.5.2.  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 number

    PM97286

  • Reported component name

    WAS SIB & SIBWS

  • Reported component ID

    620800101

  • Reported release

    850

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2013-09-18

  • Closed date

    2013-12-11

  • Last modified date

    2013-12-11

  • 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

    WAS SIB & SIBWS

  • Fixed component ID

    620800101

Applicable component levels

  • R850 PSY

       UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEQTP","label":"WebSphere Application Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"850","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
28 April 2022