PM91162: VERY HIGH DB2 CL2 CPU TIME IN ACCOUNTING RECORDS AFTER A TRAN WITH UDF DID ROLLBACK.

A fix is available

Subscribe

You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • Very high DB2 CL2 CPU time (incorrectly) reported in accounting
    records after a tran with a UDF did a rollback. The CL1 CPU
    time is low. The ET is also low.
    Possible scenario:
    A tran calls a UDF. The UDF executes an SQL statement, and
    returns. The transaction issues a rollback. Then a
    "New User" call is issued before the UDF could be properly
    closed. This can lead to DB2 clocking the class 2 times under
    the wrong agent.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All users of DB2 for z/OS.                   *
    ****************************************************************
    * PROBLEM DESCRIPTION: This APAR addresses the following 2     *
    *                      problems:                               *
    *                                                              *
    *                      1. An ABEND0C4 in CSECT DSNWAAPI when   *
    *                      executing an IFI READA request with     *
    *                      IFCARA64 bit set to ON.                 *
    *                                                              *
    *                      2. A very high CLASS 2 time can be      *
    *                      displayed in the IFCID accounting       *
    *                      record when a rollback is issued        *
    *                      against a transaction that performed    *
    *                      a UDF.                                  *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    1. When an IFI READA request is issued with IFCARA64 bit set
    to ON, DB2 will assume that the first 8 bytes contain the
    64 bit address of the IFI return area to be used. However,
    this value is incorrectly copied from into internal DB2 buffer
    causing a subsequent ABEND0C4 in CSECT DSNWAAPI.
    
    2. When a UDF is involved in a rollback, the end of transaction
    time is clocked under a different agent structure. As a result,
    calculation to obtain the total CLASS 2 accounting time will be
    performed using an uninitialized start value.  This will result
    in an incorrect total CLASS 2 accounting value.
    

Problem conclusion

  • 1. Corrected the DB2 logic that handles the 64 bit value of
    the IFI return area when IFCARA64 bit is ON.
    
    2. Corrected the DB2 logic that calculates the total CLASS 2
    time for transactions that were involved in UDF and were
    rolled back. DB2 will no longer use uninitialized value for
    this calculation.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM91162

  • Reported component name

    DB2 OS/390 & Z/

  • Reported component ID

    5740XYR00

  • Reported release

    910

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2013-06-14

  • Closed date

    2013-12-16

  • Last modified date

    2014-02-05

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

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

    UI13611 UI13613 UI13614

Modules/Macros

  • DSNDQW02 DSNTLDEA DSNTLSUS DSNWAAPI DSNWVSR1
    

Fix information

  • Fixed component name

    DB2 OS/390 & Z/

  • Fixed component ID

    5740XYR00

Applicable component levels

  • RA10 PSY UI13611

       UP14/01/10 P F401

  • RB10 PSY UI13613

       UP14/01/10 P F401

  • R910 PSY UI13614

       UP14/01/10 P F401

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.



Rate this page:

(0 users)Average rating

Add comments

Document information


More support for:

DB2 for z/OS

Software version:

910

Reference #:

PM91162

Modified date:

2014-02-05

Translate my page

Machine Translation

Content navigation