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PI25988: ISDAEMON PROPERTY OF WORKMANAGER THREADS IN BATCH CONTEXT

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You can track all active APARs for this component.

 

APAR status

  • Closed as new function.

Error description

  • The Work Manager starts jobs using isDaemon flag set to true on
    distributed systems. Therefore, thread growth cannot be
    controlled at the endpoints level. On z/OS, this is not the
    case because the isDaemon flag is set to false
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  Users of the batch function of IBM          *
    *                  WebSphere Application Server V8.5.5 on      *
    *                  distributed operating systems               *
    ****************************************************************
    * PROBLEM DESCRIPTION: On distributed operating systems, the   *
    *                      batch function is configured to         *
    *                      always obtain daemon threads for        *
    *                      asynchronous run of batch-related       *
    *                      work in an endpoint server.  This       *
    *                      does not allow the use of WorkManager   *
    *                      thread pool settings to constrain the   *
    *                      amount of work running simultaneously   *
    *                      in an endpoint.                         *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    A thread can be obtained from a WorkManager as either a daemon
    or non-daemon thread. Only non-daemon threads, however, are
    counted against the WorkManager thread pool limits. So with
    the batch function running in the endpoint server exclusively
    using daemon threads (on distributed operating systems), the
    opportunity to use WorkManager settings like "Maximum Number
    Of Threads" to constrain the amount of concurrent work
    running in the server is not available.
    This could lead to other failures like exhausting memory,
    connection pools, or other resources.
    

Problem conclusion

  • A new environment variable was introduced to offer the option
    of obtaining non-daemon WorkManager threads within the
    endpoint server, while preserving the existing behavior by
    default.
    
    This environment variable is:
    
      GRID_ENDPOINT_USE_DAEMON_THREAD
    
    If set to 'false', the batch function will obtain a non-daemon
    WorkManager thread, which will therefore be counted against
    thread pool limits.
    
    If not set or set to 'true', the batch function will use
    daemon WorkManager threads not counted against thread pool
    limits.
    
    The fix for this APAR is currently targeted for inclusion in
    fix pack 8.5.5.4.  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

    PI25988

  • Reported component name

    WEBSPHERE APP S

  • Reported component ID

    5724J0800

  • Reported release

    850

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2014-09-18

  • Closed date

    2014-11-06

  • Last modified date

    2014-11-06

  • 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

    WEBSPHERE APP S

  • Fixed component ID

    5724J0800

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":"8.5","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
28 April 2022