PM76445: UNEXPECTED STATUS 'FM' STATFM RETURED ON HALDB PARTITIONED BY KEYSTRING AND PARTITION SELECTION EXIT

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Customer added partitions to a HALDB which is partitioned by
  PSEXIT and keystring input from DBRC. After adding some
  partitions, applications received unexpected 'FM' status
  codes ( partitioning error ) accessing partitions with
  partition IDs near the end of the range - there were 288
  partitions. Diagnostics showed the user-written partition
  selection exit was being passed the expected parameters and
  was returning the correct partition ID. Further analysis
  determined that the binary search routine in DFSPSEL0 which is
  used to locate an entry in the partition index table which
  associates the partition ID with a Partition Table Entry ( PTE )
  failed to locate the correct entry although the entry was in
  the table in the expected location. The defect appears to
  have been present in the original IMS V7 logic.
  

Local fix

• Adding dummy partitions ( at least 8 ) to the end of the
  range will make the lower partitions accessible.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All IMS V11 HALDB users using a partition    *
  *                 selection exit ( PSE ).                      *
  ****************************************************************
  * PROBLEM DESCRIPTION: Invalid STATUSFM can be returned to     *
  *                      the application program when accessing  *
  *                      a HALDB that uses a partition selection *
  *                      exit.                                   *
  ****************************************************************
  * RECOMMENDATION: INSTALL CORRECTIVE SERVICE FOR APAR/PTF      *
  ****************************************************************
  When accessing a HALDB that uses a partition selection exit an
  unexpected / invalid STATUSFM can sometimes be returned to the
  application.   The partition selection exit returns a partition
  id.  A binary search routine in DFSPSEL0 then searches the
  partition table entries ( PTE ) to determine if the selected
  partition id is a valid entry in the partition id table.  Based
  on the number of partitions defined, the binary search routine
  can sometimes calculate an address beyond the end of the table,
  causing an unexpected STATUSFM to be returned even though the
  selected partition id entry is valid and in the table.
  
  Additional Symptom: If the address calculated by the binary
                      search routine is beyond the end of the
                      partition entry id table and the address
                      is not owned by / available to the
                      application and/or IMS, an  ABEND0C4 /
                      ABENDS0C4 can also occur.
  
  Additional keywords: DFSPTE STATFM FMSTAT FMSTATUS FM PTXELN
                       PTXPID PTXENT
  

Problem conclusion

• GEN:
  KEYWORDS:
  
  *** END IMS KEYWORDS ***
  The following module has been modified to correct the reported
  problem:
  
  ************
  * DFSPSEL0 *
  ************
  Code has been modified in routine PSUSERX to resolve the
  problem.  The new low entry used by the binary search
  routine to calculate the next search entry has been changed
  so that no entries in the table are incorrectly skipped.
  

Temporary fix

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

Comments

APAR Information

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

  PM76346

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

  UK83599

Modules/Macros

• DFSPSEL0
  

Fix information

• Fixed component name

  IMS V11

• Fixed component ID

  5635A0200

Applicable component levels

• R100 PSY UK83599

     UP12/11/21 P F211 Ž

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.