IC67205: SETTING PRIORITY OF EDU VIA DB2_RESOURCE_POLICY EDU_PRIORITY DOESN'T WORK ON LINUX

DB2 Version 9.8 Fix Pack 3 for AIX and Linux
DB2 Version 9.8 Fix Pack 4 for AIX and Linux
DB2 Version 9.8 Fix Pack 5 for AIX and Linux

APAR status

• Closed as program error.

Error description

• Setting priority of an EDU (DB2's engine thread) via
  DB2_RESOURCE_POLICY EDU_PRIORITY doesn't work on Linux.  For
  example, given the following setting,
  
  >> db2set
  DB2_RESOURCE_POLICY=/home/db2inst1/loggerpri.cfg
  >> cat loggerpri.cfg
  <RESOURCE_POLICY>
     <SCHEDULING_POLICY>
        <PRIORITY_VALUE>75</PRIORITY_VALUE>
        <EDU_PRIORITY>
           <EDU_NAME>db2loggw</EDU_NAME>
           <PRIORITY_VALUE>60</PRIORITY_VALUE>
        </EDU_PRIORITY>
     </SCHEDULING_POLICY>
  </RESOURCE_POLICY>
  
  All EDUs should have the priority of 75, except the db2loggw
  (log writer), which should have 60.  However, none of them has
  any priority change.  This APAR will address this problem.
  
  Note that one can view the priority of DB2 EDUs by
  cross-referencing 'ps -lLfp <PID of db2sysc>' and 'db2pd -edus'.
  
  Also note that changing priority of EDUs can greatly impact the
  overall performance of DB2 as well as the server both positively
  and negatively.  Only experienced DBAs should make use of it
  after a large amount of tests.
  

Local fix

• To change the priority of DB2 EDU's without DB2_RESOURCE_POLICY,
  one can manually run renice command.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users using Workload Manager in Linux platform               *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * Same as ERROR DESCRIPTION                                    *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Fixed in DB2 9.8 Fix Pack 3.  Upgrade to DB2 9.8 Fix Pack 3  *
  * or higher.                                                   *
  ****************************************************************
  

Problem conclusion

• Same as ERROR DESCRIPTION
  

Temporary fix

Comments

APAR Information

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

  IC66944

• 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

• R980 PSN

     UP