PI84430: REORG UTILITY HANG 17/07/27 PTF PECHANGE

APAR status

• Closed as program error.

Error description

• REORG utility reload subtask hang.
  Additional keywords: ZSA3
  

Local fix

• n/a
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All DB2 11 for z/OS with PI73882/UI44914                     *
  * applied and DB2 12 for z/OS users of the                     *
  * LOAD and REORG utilities and a zIIP                          *
  * configured and all DB2 12 for z/OS users                     *
  * of LOAD PARALLEL with CONSTANT.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * With a System z Integrated                                   *
  * Information Processor (zIIP)                                 *
  * configured and the REORG or                                  *
  * LOAD utilities are run on DB2                                *
  * 12 for z/OS or DB2 11 for z/OS                               *
  * with PI73882/UI44914 applied,                                *
  * two problems can occur:                                      *
  *                                                              *
  * 1. REORG or LOAD hang when run on a                          *
  * table space using partition                                  *
  * parallelism with an embedded copy.                           *
  *                                                              *
  * 2. REORG hang when run on a                                  *
  * non-partitioned table space and a                            *
  * STOP DB2 command is issued during                            *
  * the UNLOAD phase.                                            *
  *                                                              *
  * Also, on DB2 12 for z/OS, LOAD                               *
  * PARALLEL using CONSTANT on a                                 *
  * field-specification results in                               *
  * ABEND0C4 RC00000038                                          *
  * LOC=DSNUTILA.DSNUGSTA and ABEND04E                           *
  * RC00E20005 LOC=DSNUGSTA.DSNSVBK                              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply corrective PTF when available.                         *
  ****************************************************************
  User ran a REORG of a partitioned table space with an embedded
  copy, a System z Integrated Information Processor (zIIP)
  configured, and PI73882/UI44914 applied.  The job hung and had
  to be cancelled.
  
  A timing window exists where there are multiple RELOAD tasks in
  LOAD or REORG, running on different partitions and attempting
  to write data pages to the embedded copy, with a zIIP
  configured.  In this timing window the embedded copy subtask
  can issue a RESUME to wake up a suspended RELOAD task but
  issue it to the wrong task, causing the next task that suspends
  to miss a resume and hang.
  
  User ran a REORG of a non-partitioned table space with multiple
  indexes, a System z Integrated Information Processor (zIIP)
  configured, and PI73882/UI44914 applied.  A STOP DB2 command
  was issued while the job was in the UNLOAD phase.  MSGDSNU006I
  DB2 SYSTEM xxxx HAS NOT BEEN STARTED was issued as each index
  sort and build task were started in the RELOAD phase, but the
  job hung and had to be cancelled.
  
  When a REORG running on a non-partitioned table space, or not
  using unload/reload parallelism for any other reason, and is in
  the UNLOAD phase when a STOP DB2 command is issued, the
  subtasks attached in the RELOAD phase to sort the index keys
  cannot connect to DB2.  The main task was not detecting that
  those tasks had never started, and was suspending, causing the
  hang.
  
  LOAD PARALLEL using CONSTANT on a field-specification failed to
  initialize an internal flag for subtask processing resulting in
  ABEND0C4 RC00000038 DSNUTILA.DSNUGSTA +22B8 OFFSET22B8 or
  ABEND04E RC00E20005 DSNUGSTA.DSNSVBK  +1AEE OFFSET1AEE.
  

Problem conclusion

• LOAD and REORG have been modified to ensure that the embedded
  copy subtask issues a resume to the correct suspended task.
  
  REORG has been modified to check that the index key sort tasks
  have not prematurely terminated before suspending.
  
  Code has been changed to correct the problem in LOAD PARALLEL
  with CONSTANT.
  

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:

  UI49780 UI49781

Modules/Macros

• DSNUREPG DSNUSSIT DSNUGUCA DSNURSIT DSNURISI DSNURPCT DSNURMPG
  DSNURWBR DSNURIS2 DSNURPIB DSNUGUTC DSNUCRIB DSNURWBF
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RB10 PSY

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