PM91547: ENABLING APAR FOR THE PORTION OF APAR PM69760

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• ENABLING APAR FOR THE PORTION OF APAR PM69760 THAT DEALS WITH
  SCA REBUILD TIMEOUT WHILE MAINLINE DBET UPDATE IS IN NOTIFY EXIT
  

Local fix

• N/A
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All DB2 10, DB2 9 and DB2 V8 for z/OS data   *
  *                 sharing users of the z/OS SETXCF REBUILD     *
  *                 command when issued against SCA              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Timeout MSGDSNT376I MSGDSNT501I with    *
  *                      RC00C900C0 TYPE00002105 may occur in    *
  *                      data sharing when a REBUILD of the SCA  *
  *                      structure is issued (e.g.               *
  *                      SETXCF START,REBUILD,STRNM=DSNCAT_SCA), *
  *                      resulting in stoppage of the rebuild,   *
  *                      with messages MSGDSN7504I, MSGIXC522I   *
  *                      and MSGIXC521I, caused by concurrent    *
  *                      mainline DBET updater that happens to   *
  *                      be in the notify exit path              *
  *                                                              *
  *                      Please note:                            *
  *                      PM91547 is the enabling APAR for a      *
  *                      portion of APAR PM69760's code. This    *
  *                      enablement was originally shipped in    *
  *                      APAR PM74803 however, coincidentally    *
  *                      the functionally unrelated PE-fixer     *
  *                      APAR PM77066 happened to be based on    *
  *                      the aforementioned preconditioning and  *
  *                      enabling APARs. APAR PM91546 has been   *
  *                      provided in order to spare users from   *
  *                      the burden of applying the              *
  *                      preconditioning APAR PM69760 on all     *
  *                      members of a data sharing group just to *
  *                      get to apply the PE-fixer APAR PM77066. *
  *                      APAR PM91546 temporarily removed the    *
  *                      enabling support that was originally    *
  *                      in APAR PM74803. PM91547 now restores   *
  *                      the enablement.                         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  REBUILD of the SCA structure may experience a timeout on
  resource type 00002105 when running concurrently with
  database exception table (DBET)-heavy activity such as
  utility workloads that turn on/off various DBET states like
  UTRW, RBDP etc.
  
  The following sample illustrates the issue:
  ----------------------------------------------------------------
  DSNT376I  - PLAN=BCT      WITH 398
          CORRELATION-ID=014.RBDBET01
          CONNECTION-ID=V91A
          LUW-ID=DSNCAT.SYEC1DB2.CA3071BF1397
          THREAD-INFO=SYSOPR:*:*:*
          IS TIMED OUT. ONE HOLDER OF THE RESOURCE IS PLAN=
  WITH
          CORRELATION-ID=020.JOBSTO07
          CONNECTION-ID=V91A
          LUW-ID=DSNCAT.SYEC1DB2.CA3071B10954=7
          THREAD-INFO=SYSOPR:*:*:*
          ON MEMBER V91A
  
  DSNT501I  - DSNILMCL RESOURCE UNAVAILABLE 399
             CORRELATION-ID=014.RBDBET01
             CONNECTION-ID=V91A
             LUW-ID=DSNCAT.SYEC1DB2.CA3071BF1397=0
             REASON 00C900C0
             TYPE 00002105
             NAME INTERNAL LOCK 05
  
  DSN7504I  - DSN7LST2 400
  SCA STRUCTURE DSNCAT_SCA REBUILD UNSUCCESSFUL. REASON CODE =  8.
  
  IXC522I REBUILD FOR STRUCTURE 401
  DSNCAT_SCA IS BEING STOPPED
  TO FALL BACK TO THE OLD STRUCTURE DUE TO
  CONNECTOR SPECIFIC REASON
   USER CODE: 00000008
  
  IXC521I REBUILD FOR STRUCTURE DSNCAT_SCA 405
  HAS BEEN STOPPED
  ----------------------------------------------------------------
  
  The reason for the timeout of the SCA REBUILD is that a mainline
  DBET updater (e.g. a utility) is suspended (while holding the
  DBET hash lock) by the SCA REBUILD process. When the SCA REBUILD
  tries to obtain the same lock, it cannot do so because the
  holder is suspended and therefore the SCA REBUILD times out.
  
  APAR PM91547 is particularly for the timing window when the SCA
  REBUILD tries to obtain the DBET hash lock while a mainline DBET
  updater is in the notify exit path.
  

Problem conclusion

• Code has been changed to adjust the serialization scheme
  between mainline DBET updaters and the SCA REBUILD process.
  
  APAR PM91547 is the enabling APAR for a portion of APAR PM69760.
  APAR PM91547 should be applied only after APAR PM69760 has been
  applied on all data sharing members.
  
  Additional keywords: DB2DSHR SYSPLEXDS
  

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:

  UK97603 UK97604 UK97605

Modules/Macros

• DSNIDBEL DSNIDBGN DSNIDBGR DSNIDBNG
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RA10 PSY UK97603

     UP13/10/02 P F310

• R810 PSY UK97604

     UP13/10/02 P F310

• R910 PSY UK97605

     UP13/10/02 P F310

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.