PM71866: SIMPLE OR CLASSIC PARTITIONED TABLESPACE EXTENDS RAPIDLY

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Customer migrated from V8 to V10. They find simple tablespaces
  extend quite rapidly although most of the data pages have only
  holes and can not be reused.
  Lab can recreate the same problem with classic partition table
  space.
  The spacemap page was not updated correctly after delete.
  The problem is only under V10.
  

Local fix

• Customer can alter the simple tablespace to a segmented table
  space to avoid such problem.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All DB2 10 for z/OS (CM and above) users of  *
  *                 non-segmented table spaces (simple table     *
  *                 spaces or classic-partitioned table spaces)  *
  ****************************************************************
  * PROBLEM DESCRIPTION: Non-segmented table space may grow      *
  *                      rapidly due to insert failing to reuse  *
  *                      deleted space                           *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  In DB2 10, for non-segmented table spaces, the first SQL DELETE
  against a full page mistakenly skip to update the space map
  page. According to the non-updated space map page, the data page
  still remain full incorrectly.
  
  As a result, a subsequent insert looked for space in a different
  page, resulting in unnecessary growth to the table space.
  
  If after the first SQL DELETE against a full page came another
  SQL DELETE, depending on the space situation on the page, the
  second SQL DELETE may or may not drive update of the space map
  page. Therefore, the problem of 'unupdated' space map page could
  continue even through several SQL DELETEs.
  
  The problem is more likely to happen in table spaces that have a
  lower MAXROWS value and small row sizes.
  

Problem conclusion

• DB2 code has been modified to make sure that the first SQL
  DELETE against a full page properly updates the space map page
  so that a subsequent insert can reuse the deleted space.
  
  Additional keywords: SQLDELETE SQLINSERT
  

Temporary fix

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

Comments

APAR Information

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

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

  UK83061

Modules/Macros

•    DSNIDILS DSNIDLEO
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RA10 PSY UK83061

     UP12/11/13 P F211

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.