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IC81831: DB2 PAGE CLEANERS MAY RECEIVE SIG 11 WHEN 'DB2_USE_ALTERNATE_PAG E_CLEANING=ON' AND 'SET WRITE SUSPEND/RESUME' IS USED

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APAR status

  • Closed as program error.

Error description

  • While the cleaner was handling the pages list, a 'set write
    suspend' came in and prevented pages to be written.
    This sent the cleaner into sleep. When it resumes after a 'set
    write resume' has been issued, it assumes the current list can
    only be a dirty list.
    Such that the page cleaner will trap with invalid pointer
    access.
    
    The trap file would show a stack trace similar to the one below
    
    .sqlbClnrCheckAndPause.fdpr.clone.1805__FP12SQLB_CLNR_CBPb +
    0x2B8
    sqlbClnrEntryPoint__FP12sqbPgClnrEdu + 0xD28
    sqlbClnrEntryPoint__FP12sqbPgClnrEdu + 0x24
    RunEDU__12sqbPgClnrEduFv + 0x34
    __9sqzEDUObjFv + 0x1F0
    sqloEDUEntry + 0x260
    
    It might vary because of the way the compiler generated the
    code. The real stack, however, should be the following (only
    showing the top part):
    
    sqlbClnrCheckAndPause()
    sqlbClnrFindWork()
    sqlbClnrEntryPoint()
    sqbPgClnrEdu::RunEDU()
    

Local fix

  • Disabling APC (setting DB2_USE_ALTERNATE_PAGE_CLEANING to NO)
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * all platforms                                                *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * upgrade to db2 v97fp6                                        *
    ****************************************************************
    

Problem conclusion

  • The problem was first fixed in DB2 LUW Version 9.7 Fix Pack 6
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC81831

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    970

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-03-05

  • Closed date

    2012-05-22

  • Last modified date

    2012-05-22

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

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

    IV16771 IC84499

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • R970 PSN

       UP

  • R970 PSY

       UP



Document information

More support for: DB2 for Linux, UNIX and Windows

Software version: 9.7

Reference #: IC81831

Modified date: 22 May 2012