PH67634: CONCURRENT REORG JOBS COLLECTING INLINE STATISTICS USING PROFILE CAN GET A DEADLOCK DSNT500I RC00C90088 ON DSNDB06.SYSSTATS ROWS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Customer experiencing a deadlock on DSNDB06.SYSSTATS between
  two REORG jobs which collect inline statistics on different
  partitions of the same tablespace using a PROFILE.
  
  The deadlock happens to be on a SYSIBM.SYSCOLDIST row:
  DSNT375I  - PLAN=DSNUTIL WITH
       CORRELATION-ID=jobname1 CONNECTION-ID=UTILITY
       ...
       IS DEADLOCKED WITH PLAN=DSNUTIL WITH
       CORRELATION-ID=jobname2 CONNECTION-ID=UTILITY
  
  DSNT500I  - DSNUGRAR RESOURCE UNAVAILABLE
       REASON 00C90088 TYPE 00000304
  
       NAME DSNDB06 .SYSSTATS.X'0194A6' '.X'6B'
  
  During USE PROFILE execution, the statistics which are
  not included in the profile are deleted. When the rows are
  deleted from the SYSIBM.SYSCOLDIST catalog table, it is
  possible to get a deadlock as exclusive locks are obtained on
  the catalog table.
  

Local fix

• BYPASS/CIRCUMVENTION:
  Rerun the Reorg
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All Db2 13 for z/OS utility users of         *
  *                 concurrent RUNSTATS or inline STATISTICS     *
  *                 with USE PROFILE                             *
  ****************************************************************
  * PROBLEM DESCRIPTION: ABEND04E RC00E40213 DSNUSEOF            *
  *                      OFFSET0DF02 with MSGDSNT500I            *
  *                      RC00C90088 TYPE 00000304 DEADLOCK       *
  *                      between 2 concurrent PARTLEVEL REORG    *
  *                      TABLESPACE LIST STATISTICS USE          *
  *                      PROFILE jobs.                           *
  ****************************************************************
  * RECOMMENDATION: Apply corrective PTF when available          *
  ****************************************************************
  When the user executed concurrent partition level REORG
  jobs with TABLESPACE LIST STATISTICS USE PROFILE, the
  utility encountered a deadlock and issued DSNT500I message
  with RC00C90088 RESOURCE UNAVAILABLE DSNDB06.SYSSTATS.
  The REORG abended with an ABEND04E RC00E40213
  DSNUSEOF +x'0DF02'.
  
  During USE PROFILE execution, the statistics which are
  not included in the profile are deleted. When the rows are
  deleted from the SYSIBM.SYSCOLDIST catalog table, it is
  possible to get a DEADLOCK as exclusive locks are obtained on
  the catalog table.
  
  The aforementioned problem can also occur during RUNSTATS
  TABLESPACE USE PROFILE or LOAD utility with USE PROFILE
  STATISTICS processing.
  
  ADDITIONAL SYMPTOMS
  MSGDSNT375I  DSNT375I
  

Problem conclusion

• Code was modified to reduce contention by deleting rows from
  following catalog tables that have timestamps earlier than the
  current job's timestamp:
  SYSIBM.SYSCOLDISTSTATS
  SYSIBM.SYSCOLDIST
  SYSIBM.SYSKEYTGTDISTSTATS
  SYSIBM.SYSKEYTGTDIST
  

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:

  UO06801

Modules/Macros

• DSNUSEF2 DSNUSEOF
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RD10 PSY UO06801

     UP26/02/21 P F602

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.