PK78796: DBRF GETS ABEND0C4 FOR AN EXTENDED-FORMAT VSAM DATA SET DURING TSO ISPF SESSION

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• When DB Repair Facility processes an extended-format VSAM data
  set on interactive session, it shows an incorrect data or causes
  ABENDS0C4.
  This problem happens when SMB (System Managed Buffering) is
  enabled for the extended-format VSAM data set.
  SMB buffer storage is allocated above 16MB, but DB Repair
  Facility runs in AMODE=24.
  Therefore, DB Repair Facility refers data on incorrect address,
  and shows the incorrect data or causes ABEND0C4.
  

Local fix

• N/A
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: IBM IMS Database Repair Facility for Z/OS    *
  *                 Version 1 Release 2 (FMID=H22K120) users     *
  *                 who use an extended-format VSAM data set.    *
  ****************************************************************
  * PROBLEM DESCRIPTION: When Database Repair Facility processes *
  *                      an extended-format VSAM data set, it    *
  *                      shows an incorrect data, or gets        *
  *                      ABENDS0C4.                              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  VSAM can use system managed buffering (SMB) technique for the
  extended-format VSAM data set as a Record Access Bias
  specification in the SMS data class.
  The use of SMB can be override in JCL DD statement or When the
  VSAM file is defined as SMB enabled, VSAM allocates buffer
  spaces above 16M. On the other hands, Database Repair Facility
  runs in AMODE=24.
  When Database Repair Facility reads the VSAM and refers the
  records in the buffer, it recognizes the buffer address in
  24-bit addressing incorrectly.
  This is why Database Repair Facility shows incorrect data as the
  VSAM record or Database Repair Facility gets abend 0C4.
  This problem occur in both batch mode and Interactive (ISPF)
  mode DBRF. In case of batch mode, this problem can be avoid by
  coding RMODE31=NONE in the JCL AMP parameter.
  

Problem conclusion

• The module FABZVZAP has been modified to access a buffer in
  AMODE=31.
  And, REXX Modules FABZMAIN has been modified to display the
  recent APAR number PK78796.
  120Y
  FABZMAIN
  FABZVZAP
  

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:

  UK43340

Modules/Macros

• FABZMAIN FABZVZAP
  

Fix information

• Fixed component name

  IMS DATABASE RE

• Fixed component ID

  5655E0300

Applicable component levels

• R120 PSY UK43340

     UP09/01/22 P F901

Fix is available

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