PK12483: ENTERPRISE PL/I REGIONAL(1) I/O PERFORMANCE IMPROVEMENT

A fix is available

Subscribe

You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • Improve the performance of Enterprise PL/I REGIONAL(1) I/O.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All Enterprise PL/I users who use            *
    *                 REGIONAL(1) files.                           *
    *                                                              *
    ****************************************************************
    * PROBLEM DESCRIPTION: Enterprise PL/I REGIONAL(1) record I/O  *
    *                      performance and functional enhancement. *
    *                                                              *
    ****************************************************************
    * RECOMMENDATION: Apply the provided PTF.                      *
    *                                                              *
    ****************************************************************
    This APAR provides a new interface between Enterprise PL/I and
    Data Management in the handling of REGIONAL(1) files. The main
    purpose is to enhance performance but there are some functional
    enhancements as well.
    

Problem conclusion

  • The handling of REGIONAL(1) files was changed to use more direct
    calls to DFSMS. The results are enhanced usability and shorter
    I/O paths leading to better performance.
    
    The following documentation changes are also being made:
    
    Enterprise PL/I for z/OS Programming Guide (SC27-1457-05)
    
    Chapter 6. Using data sets and files
      Associating data sets with files under z/OS UNIX
        Specifying characteristics using DD_DDNAME environment
        variables
          Add the following after the RECCOUNT description:
    
          Note: Under z/OS, it is recommended to omit the TITLE
          option with both the /filespec parameter and RECCOUNT
          parameter for improved functionality and performance of
          REGIONAL(1) data sets. In such a case, the number of
          records that will be loaded into the file depends on the
          space allocated to the first extent of the data set. See
          Chapter 9 "Defining and using regional data sets" for
          additional information.
    
      Establishing data set characteristics
        Specifying characteristics in the ENVIRONMENT attribute
          The ENVIRONMENT attribute
            Table 13. Attributes of PL/I file declarations
    
            Delete the Buffered column under Sequential Regional
              files.
            Remove the Regional header under Sequential files.
            Remove the Unbuffered header and replace it with
              Regional.
    
          Data set types used by PL/I record I/O
            Table 14. A comparison of data set types available to
                      PL/I record I/O
              Change the Yes, 2 under the REGIONAL(1) column and
                the DELETION row to Yes, 1 since the space is
                reusable
    
    Chapter 9. Defining and using regional data sets
      Table 20. Statements and options allowed for creating and
                accessing regional data sets
        Table Row 1
          Remove the word BUFFERED from SEQUENTIAL OUTPUT BUFFERED
        Table Row 2
          Remove the entire row SEQUENTIAL OUTPUT
        Table Row 3
          Remove the word BUFFERED from SEQUENTIAL INPUT BUFFERED
        Table Row 4
          Remove the entire row SEQUENTIAL INPUT
        Table Row 5
          Remove the word BUFFERED from SEQUENTIAL UPDATE BUFFERED
        Table Row 6
          Remove the entire row SEQUENTIAL UPDATE
        Table Row 10 (the one containing UNLOCK)
          Remove the entire row DIRECT UPDATE
    
      Defining files for a regional data set
        Add the following after the DCL statement syntax:
          Since BUFFERED and UNBUFFERED will be treated the same
          for REGIONAL(1) data sets, either option can be specified
          in the ENV option. For example, the FROM option is not
          required on a REWRITE for a SEQUENTIAL UNBUFFERED file
          and the LOCATE statement is allowed for OUTPUT SEQUENTIAL
          data sets even if UNBUFFERED is specified.
    
        Specifying ENVIRONMENT options
          The ENVIRONMENT options applicable to regional data sets
          are:
    
          REGIONAL(1)
          F
          RECSIZE(record-length)
          BLKSIZE(block-size)
          SCALARVARYING
    
          Add the following after the REGIONAL(1) option
          description:
    
            RECSIZE(record-length)
            BLKSIZE(block-size)
              If both RECSIZE and BLKSIZE are specified, they must
              specify the same value.
    
        Using keys with REGIONAL data sets
          Remove the first sentence from the last paragraph that
          discusses the KEYLENGTH option and the KEYLEN
          subparameter.
    
      Using REGIONAL(1) data sets
        Creating a REGIONAL(1) data set
          Delete the third paragraph (which starts with "If you
          create a data set using a buffered file,").
    
        Creating a REGIONAL(1) data set
          Example
            Change the OPEN statement to (the TITLE option is
            removed):
              OPEN FILE(NOS);
    
      Essential information for creating and accessing regional
      data sets
        Change the second bullet in the second paragraph to:
          Block size: You can specify the block size either in your
          PL/I program (in the BLKSIZE option of the ENVIRONMENT
          attribute) or in the DD statement (BLKSIZE subparameter).
          If you do not specify a record length, unblocked records
          are the default and the record length is determined from
          the block size. If you do specify a record length, it
          must be equal to the block size.
    
        Delete the third bullet (RECCOUNT) in the second paragraph.
    
        Change the first sentence of the last paragraph to:
    
          In the DCB parameter, if you specify the DSORG parameter,
          you must specify the data set organization as direct by
          coding DSORG=DA.
    
        Delete the fourth paragraph below table 21 (the one that
        discusses the OPTCD=L DD subparameter).
    
    PUBS CLOSING CODE: DEVCHNG
    

Temporary fix

Comments

APAR Information

  • APAR number

    PK12483

  • Reported component name

    LE VA PL/I

  • Reported component ID

    568819806

  • Reported release

    707

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2005-09-26

  • Closed date

    2006-03-17

  • Last modified date

    2013-06-05

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

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

    UK12732 UK12733 UK12734 UK12735

Modules/Macros

  • IBMPOCAA IBMPODCB IBMPOIOA IBMPOPBA IBMPOPFA
    IBMPOPNA IBMPRARA IBMP3DMP IBMVDCB  IBMVENTY IBMVFCO  IBMVIOA
    IBMVTCA  IBMVXNAM IBMVXPRL JLE7307Z JLE7308Z JLE7309Z JLE7320Z
    

Fix information

  • Fixed component name

    LE VA PL/I

  • Fixed component ID

    568819806

Applicable component levels

  • R707 PSY UK12732

       UP06/03/22 P F603

  • R708 PSY UK12733

       UP06/03/22 P F603

  • R709 PSY UK12734

       UP06/03/22 P F603

  • R720 PSY UK12735

       UP06/03/22 P F603

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.



Rate this page:

(0 users)Average rating

Document information


More support for:

z/OS family

Software version:

7.0.7

Operating system(s):

z/OS

Reference #:

PK12483

Modified date:

2013-06-05

Translate my page

Machine Translation

Content navigation