PH34239: CMOD IS ENHANCED TO SPECIFY INVALIDATECACHE YES WHEN RUNNING DB2 12 OR HIGHER.

Obtain the fix for this APAR.

APAR status

• Closed as unreproducible in next release.

Error description

• DB2 introduced a change in behavior during runstats. Prior to
  DB2 V12, runstats always invalidated the cache. Starting with
  DB2 12, DB2 does not invalidate the cache unless you specify
  INVALIDATECACHE YES. Due to this change, the DB2 optimizer may
  not pick the same access path, leading to poor performance of
  CMOD queries.
  
  In order to restore the prior runstats behavior, CMOD is
  being enhanced to specify INVALIDATECACHE YES when running
  DB2 12 or higher
  

Local fix

• manually run runstats outside of CMOD with INVALIDATECACHE YES
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All Content Manager OnDemand for z/OS 10.1   *
  *                 and above customers                          *
  ****************************************************************
  * PROBLEM DESCRIPTION: DB2 12 introduced a change in that      *
  *                      RUNSTATS no longer invalidates the DB2  *
  *                      statement cache.  This can cause        *
  *                      performance issues with CMOD            *
  *                      application group data tables.          *
  ****************************************************************
  * RECOMMENDATION: ARGMVSIE is changed so that if running on    *
  *                 DB2 12 or higher an INVALIDATECACHE YES      *
  *                 clause is added to the RUNSTATS command.     *
  *                 This will restore the pre-DB2 12 RUNSTATS    *
  *                 behavior.                                    *
  ****************************************************************
  DB2 12 introduced a change in that RUNSTATS no longer
  invalidates the DB2 statement cache.  This can cause performance
  issues with CMOD application group data tables.
  

Problem conclusion

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:

  UI74391 UI74394

Modules/Macros

• ARGMVSIE ARNMVSIE
  

Fix information

• Fixed component name

  CM OD Z/OS, OD/

• Fixed component ID

  5655H3900

Applicable component levels

• RA10 PSY UI74391

     UP21/03/13 P F103

• RA50 PSY UI74394

     UP21/03/13 P F103

Fix is available

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