PI49798: ABEND04E RC00E20029 DSNIDBEL DSNSVBK+X'1B5C' DURING DBET STORAGEBLOCK FREE THAT HAS ALREADY BEEN FREED.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Dump Title: D01B ABND 04E 00E20029 U=SYSOPR M=C9 C=101.SMC
  DSNSFSTG M=DSNTFRCV LOC=DSNIDBEL DSNSVBK OFFSET1B5C
  DBET notify exit issued ABEND04E RC00E20029 and caused DB2 down
  by RC00E50702 - 00E50702
  ABEND04E RC00E20029 happened when DSNIDBEL tried to free a DBET
  block because the block had been already freed.
  Additional symptoms: ABEND04E RC00C90101 00C90101 DSNIDBGC
                       ERQUAL 501A ERQUAL501A MSGDSNV086E
                       DSNV086E 00E50702 RC00E50702
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All V11 and V12 users of Db2 for z/OS                        *
  * data sharing are affected.                                   *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * ABEND04E RC00E20029 DSNIDBEL DSNSVBK                         *
  * OFFSET1B5C may occur when DBET                               *
  * incorrectly frees storage that has                           *
  * been freed previously.                                       *
  *                                                              *
  * There can be missing DBET states                             *
  * when 2 transactions change the same                          *
  * object at the same time.                                     *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply corrective PTF when available.                         *
  ****************************************************************
  In very rare situations in data sharing groups, DBET states are
  not merged correctly due to concurrency issues. This might lead
  to corrupted DBET information.
  

Problem conclusion

• The timing window has been fixed to prevent this corruption.
  
  Reason code 00C900C0 may now be written from more DBET modules
  when an internal lock is not granted. The addition of the
  database name and tablespace name (or if not available, the
  DBID.PSID) will be written as part of the resource name to aid
  in problem analysis.
  
  
  In the Codes manual (V11 GC19-4053, and V12 GC27-8847-00),
  under Appendix F. Resource types, the descriptions for
  resource 2104 and 2105 are reversed. The following
  change will be made:
  00002104  Logical partition DBET entry  DB.SP.PT
  00002105  DBET hash chain lock timeout  INTERNAL LOCK NN DB.SP
            or DBID.PSID or NONE
  
  
  Additional keywords: ZSA45 MSGDSNT501I RC00C900C0
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

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

  UI54304 UI54305

Modules/Macros

• DSNIDBNG DSNIDBLG DSNIDBNI DSNIDBPL DSNIDBDA DSNIDBRP DSNIDBLK
  DSNIDBBD DSNIDBDF DSNIDBDG DSNIDBHK DSNIDBPX DSN1LOUT DSNIDBDR
  DSN1LDET DSNIDBSE DSNIDBDW DSNIDBMC DSNIDBSI DSNIDBMF DSNIDBMG
  DSNWDFDM DSNIDBGC DSNIDBAB DSNIDBAE DSNIDBIN DSNIDBMS DSNIDBEL
  DSNIDBGN DSNILMCL DSNWDFMG
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RC10 PSY UI54304

     UP18/03/16 P F803 ¢

• RB10 PSY UI54305

     UP18/03/15 P F803 ¢

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.