IBM Support

PM30468: FOR DB2 V10 PREFETCH AND DEFERRED WRITE ZIIP RDIRECT,WLM REPORTS THE ZIIP REDIRECT UNDER MSTR REPORTING CLASS, INSTEAD OF DBM1

A fix is available

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • For DB2 V10 prefetch and deferred write zIIP rdirect,WLM reports
    the zIIP redirect under MSTR reporting class  instead of
    DBM1 reporting class.
    Additional Symptoms: ABENDS0C4 0C4 S0C4 DSNB1ABP DSNB1CBP
                         DSNB1GET DSNB1GRA DSNB1GWB or DSNB1RRR
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED: DB2 users.                                   *
    ****************************************************************
    * PROBLEM DESCRIPTION: Prefetch and deferred write CPU, when   *
    *                      running on a zIIP processor, is         *
    *                      reported under the MSTR address space   *
    *                      instead of DBM1.                        *
    *                                                              *
    *                      Buffer pool hash anchor and latch       *
    *                      storage may not be initialized to       *
    *                      zeroes when allocated, which could      *
    *                      result in:                              *
    *                        - Agents suspended in DSNVXLT0 on     *
    *                          a class 14 hash chain latch.        *
    *                        - ABEND0C4 in DSNB1ABP, DSNB1CBP,     *
    *                          DSNB1GET, DSNB1GRA, DSNB1GWB,       *
    *                          or DSNB1RRR.                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    When the enclave used for prefetch and deferred writes is
    created during DB2 startup, the home address space is MSTR,
    so zIIP CPU gets reported under that address space.
    
    The code which initializes the hash anchor and latch storage
    does not account for the possibility of the clearing instruction
    being interrupted, so some of the storage may not get cleared.
    

Problem conclusion

  • The creation of the enclave for prefetch and deferred write is
    now done under a service task whose home address space is DBM1.
    
    The code which allocates the buffer pool hash anchor and latch
    storage has been modified to ensure that it is completely
    cleared.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM30468

  • Reported component name

    DB2 OS/390 & Z/

  • Reported component ID

    5740XYR00

  • Reported release

    A10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-01-13

  • Closed date

    2011-01-31

  • Last modified date

    2011-03-02

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

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

    UK64423

Modules/Macros

  • DSNB1ABP DSNB1BVP DSNB1PM2 DSNB1WLM DSNB3WLM
    

Fix information

  • Fixed component name

    DB2 OS/390 & Z/

  • Fixed component ID

    5740XYR00

Applicable component levels

  • RA10 PSY UK64423

       UP11/02/15 P F102

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEPEK","label":"Db2 for z\/OS"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"10.1","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}},{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"10.1","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
02 March 2011