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IC80651: DB2 MAY PANIC DURING ATTEMPT TO UNFIX (SQLBUFIX) A PAGE FROM BUFFERPOOL

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • When INSPECTing a damaged object DB2 may read bad pages into the
    bufferpool without detecting them.
    
    This happens with pages that belong to the same object and
    therefore look like a valid page.
    The actual corruption is the data pages being out of sync with
    the objects EMPs.
    
    A possible sequence of events that may result in the above
    corruption and instance PANIC is:
    - a not logged operation (NLI) against an object is
    aborted/rolled back
    - the object is in drop pending state after the NLI operation
    - INSPECT with option ERROR STATE ALL is executed against the
    object
    - error SQL1224N is hit and instance is brought down
    
    A possible stack may look like following:
    
     ...
     sqlb_panic
     sqlbufix
     dartCall_sqlbUnFixPage
     dartUnfixPage
     dartScanDAT
     dartScanTable
     dartScanTablespace
     dartInspect
    
    This APAR will ensure DB2 detects the corruption upon fixing the
    page (sqlbfix) instead of successfully loading it into
    bufferpool and fail upon releasing/unfixing the page from
    bufferpool.
    

Local fix

  • 1) For objects with questionable states, do not use the FOR
    ERROR STATE ALL clause with INSPECT.
    2) For objects with questionable states, use db2dart to inspect
    them.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to DB2 Version 9.7 Fix Pack 6.                       *
    ****************************************************************
    

Problem conclusion

  • First fixed in DB2 Version 9.7 Fix Pack 6.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC80651

  • 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

    2012-01-04

  • Closed date

    2012-06-11

  • Last modified date

    2012-06-11

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

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

    IC84265

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • R970 PSN

       UP



Document information

More support for: DB2 for Linux, UNIX and Windows

Software version: 9.7

Reference #: IC80651

Modified date: 11 June 2012