IT21938: DB2DART REPORT ON A COLUMN-ORGANIZED (BLU) TABLE TAKES LONG TIMETO COMPLETE

Db2 Version 11.1 Mod 3 Fix Pack 3 for Linux, UNIX, and Windows
Db2 Version 11.1 Mod3 Fix Pack3 iFix001 for Linux, UNIX, and Windows
Db2 Version 11.1 Mod3 Fix Pack3 iFix002 for Linux, UNIX, and Windows
Db2 Version 11.1 Mod 4 Fix Pack 6 for Linux, UNIX, and Windows
Db2 Version 11.1 Mod 4 Fix Pack 5 for Linux, UNIX, and Windows
Db2 Version 11.1 Mod 4 Fix Pack 7 for Linux, UNIX, and Windows

APAR status

• Closed as program error.

Error description

• Db2dart takes a very long time (hours) to complete on a
  column-organized table whereas it completes in a short time
  (minutes) on a row-organized table with same data size.
  
  In db2dart processing, while accesing pages, the integrity
  checks made on column-organized tables are different than on
  row-organized tables.
  This integrity check referred to as cross data-index check is
  not done for row organized tables.
  
  In this cross data-index check function, we access data pages
  based on an index map created for column-organized tables. Due
  to a problem in the sequence of some sub-functions in it, we
  require to do some extra processing to reach next page. This
  extra processing is causing the delays in the db2dart
  performance as it needs to be done for each page find. So the
  time required for db2dart scales up depending on the size
  (number of pages) of the column-organized table.
  

Local fix

• Run INSPECT command instead of db2dart to inspect the
  column-organized tables.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
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  * PROBLEM DESCRIPTION:                                         *
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  * RECOMMENDATION:                                              *
  * Upgrade to Db2 11.1 Mod 3 Fix Pack 3 or higher               *
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Problem conclusion

• First fixed in Db2 11.1 Mod 3 Fix Pack 3
  

Temporary fix

Comments

APAR Information

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

  IT21149

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

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RB10 PSN

     UP