PM06735: DISABLING QUERY PARALLELISM VIA RLF DOESN'T WORK

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Customer added following rows into RLST, but the query still
  running in parallelism in SPUFI.
  
  AUTHID PLANNAME     ASUTIME LUNAME   RLFFUNC
   *       *                   *  *         *
  ------ -------- ----------- -------- -------
           DSNESPCS            ?            4
           DSNESPCS            ?            3
           DSNESPCS            ?            5
  
  Additional keywords and symptoms:
  DB2PARALL/K
  

Local fix

• Set CURRENT DEGREE = '1' to disable query parallelism
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All DB2 V8 and 9 (for z/OS) users of         *
  *                        Resource Limit Facility (RLF)         *
  *                             parallelism disablement          *
  ****************************************************************
  * PROBLEM DESCRIPTION: When RLF governing for parallelism is   *
  *                      enabled, DB2 does not correctly disable *
  *                      parallelism exploitation for qualified  *
  *                      dynamic statements.                     *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  RLF Governing can be used to disable parallelism exploitation
  when a qualified dynamic statement is being executed. However,
  this parallelism restriction by RLF does not always correctly
  disable parallelism due to an uninitialized internal variable,
  causing an unpredicted behavior in RLF parallelism disablement.
  

Problem conclusion

• DB2 code has been modified to ensure proper setting of the
  internal variable to correctly contain the information for
  parallelism disablement using RLF governor.
  .
  Additional Keywords
  predictive reactive sqlparallelism
  

Temporary fix

Comments

APAR Information

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

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

  UK57228 UK57229

Modules/Macros

• DSNTBBP  DSNTBBP2 DSNTRLPD DSNXEDP  DSNXEDS1
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• R810 PSY UK57228

     UP10/06/09 P F006

• R910 PSY UK57229

     UP10/06/09 P F006

Fix is available

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