IBM Support

PM42033: MESSAGES ON MQ SERVER NOT CONSUMED DUE TO DEADLOCK

Fixes are available

7.0.0.21: WebSphere Application Server V7.0 Fix Pack 21
7.0.0.23: WebSphere Application Server V7.0 Fix Pack 23
7.0.0.25: WebSphere Application Server V7.0 Fix Pack 25
7.0.0.27: WebSphere Application Server V7.0 Fix Pack 27
7.0.0.29: WebSphere Application Server V7.0 Fix Pack 29
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
7.0.0.35: WebSphere Application Server V7.0 Fix Pack 35
7.0.0.37: WebSphere Application Server V7.0 Fix Pack 37
7.0.0.39: WebSphere Application Server V7.0 Fix Pack 39
7.0.0.41: WebSphere Application Server V7.0 Fix Pack 41
7.0.0.43: WebSphere Application Server V7.0 Fix Pack 43
7.0.0.45: WebSphere Application Server V7.0 Fix Pack 45
7.0.0.21: Java SDK 1.6 SR9 FP2 Cumulative Fix for WebSphere
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

Subscribe

You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • Using the MQ Server feature of the Service Integration Bus,
    messages are not delivered to a consumer from a destination
    on the MQ Server queue manager.  A javacore from the JVM
    hosting the MQ Server shows the following deadlock:
    
    Thread 1:
    
    com/ibm/ws/sib/processor/impl/RMQAsynchThread.resume(RMQAsynchTh
    read.java:182)
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQConsumerKey.resumeRMQAsyncThrea
    d(RMQConsumerKey.java:280)--> waiting to lock on RMQAsynchThread
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQLocalConsumerPoint.resumeConsum
    er(RMQLocalConsumerPoint.java:1968) -->
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQLocalConsumerPoint.removeActive
    Messages(RMQLocalConsumerPoint.java:1596) --> holding a lock
    on RMQLocalConsumerPoint
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQLocalConsumerPoint.afterComplet
    ion(RMQLocalConsumerPoint.java:2057)
    ...
    
    Thread 2:
    com/ibm/ws/sib/processor/impl/RMQLocalConsumerPoint.addAsynchMes
    sage(RMQLocalConsumerPoint.java:1756) --> waiting to lock
    RMQLocalConsumerPoint
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQAsynchThread$AsynchRunnable.run
    AsynchConsumer(RMQAsynchThread.java:575(Compiled Code))
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQAsynchThread$AsynchRunnable.acc
    ess$300(RMQAsynchThread.java:197)
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQAsynchThread.start(RMQAsynchThr
    ead.java:121)---> holding a lock on RMQAsynchThread
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQConsumerKey.startRMQAsyncThread
    (RMQConsumerKey.java:229)
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQLocalConsumerPoint.internalStar
    t(RMQLocalConsumerPoint.java:1858)
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/RMQLocalConsumerPoint.start(RMQLoc
    alConsumerPoint.java:1245)
    4XESTACKTRACE at
    com/ibm/ws/sib/processor/impl/ConsumerSessionImpl.start(Consumer
    SessionImpl.java:855)
    4XESTACKTRACE at
    ...
    

Local fix

  • All messages are processed after restart of the Servant region.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  Users of the default messaging provider     *
    *                  for                                         *
    *                  IBM WebSphere Application Server using the  *
    *                  MQ Server functionality                     *
    ****************************************************************
    * PROBLEM DESCRIPTION: A deadlock prevents messages being      *
    *                      consumed from an MQ Server bus memner   *
    *                      destination                             *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    The deadlock occurs when the thread responsible for message
    retrieval runs inline with the the start of the consumer.
    This causes the lock hierachy to be broken and an ABBA
    deadlock ensues.
    

Problem conclusion

  • This APAR resolves the deadlock by ensuring that the lock
    hierarchy is observed when the thread to retrieve messages is
    run inline with the thread starting the consumer.
    
    The fix for this APAR is currently targeted for inclusion in
    fix pack 7.0.0.21.  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 number

    PM42033

  • Reported component name

    WAS SIB & SIBWS

  • Reported component ID

    620800101

  • Reported release

    300

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-06-20

  • Closed date

    2011-07-30

  • Last modified date

    2011-07-30

  • 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

  • R800 PSY

       UP



Document information

More support for: WebSphere Application Server
Service Integration Technology

Software version: 7.0

Reference #: PM42033

Modified date: 30 July 2011