12 December,2011 by Tom Collins
While troubleshooting a DB2 performance problem for Websphere Portal 6.1.0 using DB2 9.5 Enterprise Edition , one of the DB2 tuning recommendations from the Portal Tuning guide was to set MAXFILOP = 512 or higher
MAXFILOP is the Maximum database files open per application configuration parameter.
The MAXFILOP parameter defines the maximum file handles that can be opened by a database agent. If the number is to small , a CPU overhead is incurred.
To view the existing MAXFILOP value do a :
db2 get db cfg for WMMDB | grep 'MAXFILOP'
One method of assessing the right level is to monitor the Database Snapshots. If the Database Snapshots regularly show "Database Files Closed > 0" then the MAXFILOP is one configuration to increase.
To view the Database Files Closed > 0 , turn on DFT_MON_BUFPOOL with :
db2 “update dbm cfg using DFT_MON_BUFPOOL” db2 "get snapshot for database on myDB"
Look for Database Files Closed. If the Database Files Closed is greater than zero , consider increasing MAXFILOP
Author: Jack Vamvas(http://www.dba-db2.com)This is only a preview. Your comment has not yet been posted.
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