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IC64884: Multi-threaded C++ application fails to exploit connection cache in MQ leading to increased chance of IC64690 occurring.

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • A multi-threaded C++ client application creates many
    connections to the same queue manager with the same connection
    details across many threads. This could result in the symptoms
    observed in IC64690. If IC64690 is observed, this APAR should
    also be applied as it addresses conditions which increase the
    chance that IC64690 occurs.
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Any users of WebSphere MQ using multi-threaded C++ client
    applications.
    
    Platforms affected:
    Windows
    
    ****************************************************************
    PROBLEM SUMMARY:
    The problem was caused by an uninitialised MQCD structure being
    passed from the C++ layer to the C layer. Due to the
    uninitialised data, this was causing the caching algorithm to
    fail to find a MQCD match in the list of existing connections,
    despite the connection details being identical. This was then
    leading to the unnecessary creation of new cache items, one of
    the conditions which triggers IC64690 to occur.
    

Problem conclusion

  • WebSphere MQ was modified to ensure that the MQCD was
    initialised correctly within the C++ layer, thus allowing the
    cache comparison algorithm to correctly ascertain whether a
    similar connection was already in use.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
                       v7.0
    Platform           Fix Pack 7.0.1.2
    --------           --------------------
    Windows            U200316
    
    The latest available maintenance can be obtained from
    'WebSphere MQ Recommended Fixes'
    http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
    
    If the maintenance level is not yet available, information on
    its planned availability can be found in 'WebSphere MQ
    Planned Maintenance Release Dates'
    http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
    ---------------------------------------------------------------
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC64884

  • Reported component name

    WMQ WINDOWS V7

  • Reported component ID

    5724H7220

  • Reported release

    700

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2009-11-30

  • Closed date

    2009-12-17

  • Last modified date

    2009-12-17

  • 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

    WMQ WINDOWS V7

  • Fixed component ID

    5724H7220

Applicable component levels

  • R700 PSY

       UP

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Document Information

Modified date:
17 December 2009