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IT12875: CLUSTER CHANNEL STARTUP DELAYED.

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • When a message is put into a remote/cluster queue within a TMF
    user transaction, while the corresponding transmit queue is
    empty or almost empty, it can take up to 60 seconds after the
    end of the transaction until the message is transmitted. As a
    side effect automatic channel starts can also be delayed.
    

Local fix

  • Set Environment Variable MQQMSHKEEP.
    
    *** Note: The Setting for the Environment Variable is in Seconds
    and has an impact on the frequency of some housekeeping. An
    increase in CPU Utilization would be expected from the increased
    frequency of this houskeeping.
    
    The correct procedure for setting the environment variable:
    1. Freeze and stop MQS-QMGRSVR00 in Pathway
    2. Check that the process is stopped, if not stop it from TACL
    3. In Pathcom:
    ALTER MQS-QMGRSVR00,ENV MQQMSHKEEP=20
    
    To delete the environment variable for the server use the
    following syntax:
    ALTER SERVER MQS-QMGRSVR00,DELETE ENV MQQMSHKEEP
    

Problem summary

  • When a message is put into a cluster queue within
    a TMF user transaction and while the corresponding transmit
    queue is empty or almost empty, it can take up to 60 seconds
    after the end of the transaction until the message is
    transmitted. As a side effect automatic channel starts can
    also be delayed.
    

Problem conclusion

  • The WebSphere MQ product code has been corrected such that
    in the scenario above, the END TRANSACTION handling will
    catch all END TRANSACTION events instantaneously for messages
    to be transmitted to other cluster nodes.
    

Temporary fix

  • Set Environment Variable MQQMSHKEEP.
    *** Note: The Setting for the Environment Variable is in Seconds
    and has an impact on the frequency of some housekeeping. An
    increase in CPU Utilization would be expected from the increased
    frequency of this housekeeping.
    The correct procedure for setting the environment variable:
    1. Freeze and stop MQS-QMGRSVR00 in Pathway
    2. Check that the process is stopped, if not stop it from TACL
    3. In Pathcom:ALTER MQS-QMGRSVR00,ENV MQQMSHKEEP=20
    To delete the environment variable for the server use the
    following syntax:
      ALTER SERVER MQS-QMGRSVR00,DELETE ENV MQQMSHKEEP
    

Comments

APAR Information

  • APAR number

    IT12875

  • Reported component name

    WEBS MQ NSS ITA

  • Reported component ID

    5724A3902

  • Reported release

    531

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2015-12-21

  • Closed date

    2016-06-10

  • Last modified date

    2016-06-10

  • 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 MQ NSS ITA

  • Fixed component ID

    5724A3902

Applicable component levels

[{"Line of Business":{"code":"LOB36","label":"IBM Automation"},"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSFKSJ","label":"WebSphere MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"5.3.1"}]

Document Information

Modified date:
17 November 2020