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IC79285: UNDER HEAVY OLTP WORKLOADS ON AIX, SYSTEM-CPU USAGE MAY SPIKE CAUSING AN IMPACT TO DB2 PERFORMANCE.

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You can track all active APARs for this component.

 

APAR status

  • Closed as fixed if next.

Error description

  • DB2 uses a latching implementation which uses AIX thread_lock()
    / thread_unlock() APIs.
    Under very heavy workloads, when hundreds or more threads are
    waiting on and waking on the same latch/lock, it's possible for
    a spike in system-cpu usage to occur, which can significantly
    impact DB2 performance.  Spikes can last for short (minutes) or
    long (tens of minutes) duration.
    
    To enable this APAR fix on db2, the following db2 registry needs
    to be set:
    
    db2set DB2_ENABLE_THREAD_UNLOCK_EXTENDED=YES
    db2stop force
    db2start
    
    AIX Level that includes the prerequisite APAR fix
    6.1 TL06 SP7 (IV10411)
    6.1 TL07 SP2 (IV10010)
    6.1 TL08  (IV13362)
    7.1 GA SP5 (IV14638)
    7.1 TL01 SP2 (IV09962)
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to v97 fixpak 6.                                     *
    ****************************************************************
    

Problem conclusion

Temporary fix

Comments

APAR Information

  • APAR number

    IC79285

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    970

  • Status

    CLOSED FIN

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-10-19

  • Closed date

    2012-06-06

  • Last modified date

    2013-11-05

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    IT01204

Fix information

Applicable component levels

  • R970 PSY

       UP

  • RA10 PSY

       UP

[{"Line of Business":{"code":"LOB10","label":"Data and AI"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSEPGG","label":"DB2 for Linux- UNIX and Windows"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.7"}]

Document Information

Modified date:
18 September 2021