PM64499: WRONG BLOCKSIZE USED FOR THE OUTPUT DATA SET

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• When specifying a TEMPLATE statement for allocating the output
  data set and the TEMPLATE statement specifies a tape UNIT, the
  blocksize set by DB2 HPU is not relevant which usually leads to
  poor performance: CPU and elapse time and space needed for the
  output data set are unexpectedly large.
  
  The wrong blocksize used for the output data set depends on the
  RECFM expected for the output data set.
  - If a fixed length record is expected (RECFM=FB),
    the BLKSIZE is set to 512
  - If a variable length record is expected (RECFM=VB),
    the BLKSIZE is set to 1024
  
  The problem has impacts only when the expected LRECL of the
  output data set is less than the wrong BLKSIZE mentioned above.
  
  PB11579 performance
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  *                 All users of HPU 4.1                         *
  *                                                              *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  *                      When specifying a TEMPLATE statement    *
  *                      for allocating the output data set      *
  *                      and the TEMPLATE statement specifies    *
  *                      a tape UNIT, one or both of the         *
  *                      following problem occur:                *
  *                                                              *
  *                      a- the blocksize set by DB2 HPU is not  *
  *                      relevant which usually leads to poor    *
  *                      performance: CPU and elapse time and    *
  *                      space needed for the output data set    *
  *                      are unexpectedly big.                   *
  *                                                              *
  *                      b- if stacking is requested             *
  *                      (STACK YES option) and several output   *
  *                      data set are to be written to tape,     *
  *                      the same RECFM is unduly used for all   *
  *                      the data sets.                          *
  *                                                              *
  *                      The wrong blocksize used for the        *
  *                      output data set depends on the RECFM    *
  *                      expected for the output data set.       *
  *                                                              *
  *                      - If a fixed length record is expected  *
  *                      (RECFM=FB), the BLKSIZE is set to 512   *
  *                                                              *
  *                      - If a variable length record is        *
  *                      expected (RECFM=VB), the BLKSIZE        *
  *                      is set to 1024                          *
  *                                                              *
  *                      The problem has impacts only when       *
  *                      the expected LRECL of the output        *
  *                      data set is less than the wrong         *
  *                      BLKSIZE mentioned above.                *
  *                                                              *
  ****************************************************************
  * RECOMMENDATION: APPLY the PTF.                               *
  ****************************************************************
  Code has been changed to correct this condition.
  

Problem conclusion

• Apply the PTF.
  

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:

  UK79399

Modules/Macros

•    INZUTILK
  

Fix information

• Fixed component name

  DB2 HI PERF UNL

• Fixed component ID

  5697F4400

Applicable component levels

• R410 PSY UK79399

     UP12/06/12 P F206

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.