IBM Support

IT23992: Duplicate message IDs can occur when putting messages asynchronously to an MQ v9 queue manager

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APAR status

  • Closed as program error.

Error description

  • When submitting MQPUT calls using MQPMO_ASYNC_RESPONSE, or using
    a JMS client configuration which allows aysnc responses, under
    very high load duplicate message IDs are occasionally observed.
    

Local fix

  • Modify the application or JMS configuration to use synchronous
    MQPUT response.
    

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Any users putting messages asynchronously to MQ servers at
    version 9, which includes JMS applications configured to permit
    an async put response.
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    When applications are making use of asynchronous put responses,
    the MQ client must request a pre-allocation of message IDs from
    the queue manager.
    
    A logic error within these routines at the queue manager
    introduced a timing window whereby the queue manager would not
    correctly allocate a  unique range. Under high load, this could
    result in non-unique message IDs being assigned to messages.
    

Problem conclusion

  • The MQ queue manager logic has been corrected to ensure that
    appropriate pre-allocated message ID ranges are returned to
    clients using asynchronous put.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v9.0 LTS   9.0.0.5
    
    
    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

    IT23992

  • Reported component name

    IBM MQ BASE M/P

  • Reported component ID

    5724H7261

  • Reported release

    900

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2018-02-08

  • Closed date

    2018-06-28

  • Last modified date

    2018-06-28

  • 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

    IBM MQ BASE M/P

  • Fixed component ID

    5724H7261

Applicable component levels

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.0","Edition":"","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
28 June 2018