RECOMMENDATIONS SECTION

All recommendations contained in this report are based solely on the conditions which were present when the performance data was collected. It is possible that conditions which were not present at that time may cause some of these recommendations to result in worse performance. To minimize this risk, analyze data from several different days, implement only regularly occurring recommendations, and implement them one at a time.

Change the value of maxpgio from 60 to 65536. The reason for this significant change can be found in the Resource Analysis Section. This parameter can be changed by adding the following line to the /etc/system file: 'set maxpgio = 65536'. NOTE: Don't forget to check /etc/system first to see if there's already a set command modifying this tunable parameter. If there is, modify that command instead of adding another one.

Change the value of priority paging from 0 to 1. This parameter can be changed by adding the following line to the /etc/system file: 'set priority_paging = 1'. NOTE: Don't forget to check /etc/system first to see if there's already a set command modifying this tunable parameter. If there is, modify that command instead of adding another one.

Change the value of ncsize from 4236 to 5295. This change is recommended because the DNLC hit ratio, as calculated from kernel statistics, is 88.48 percent. Kernel statistics have been used instead of sar -a data because the values seen in the sar data were too low to calculate the DNLC hit ratio accurately. The low values seen in the sar -a data mean that the degree of improvement realized by implementing this recommendation is likely to be small. This parameter can be changed by adding the following line to the /etc/system file: 'set ncsize = 5295'. NOTE: Don't forget to check /etc/system first to see if there's already a set command modifying this tunable parameter. If there is, modify that command instead of adding another one. Once this change has been implemented, changes to the maxusers parameter will no longer affect ncsize.

Change the value of ufs_ninode from 4236 to 5295. This recommendation will increase the value of ufs_ninode to match the value of ncsize. Whenever a recommendation is made to increase ncsize, this program will also recommend increasing ufs_ninode to the same value. For more information, see page 309 of the second edition of Sun Performance and Tuning by Adrian Cockcroft. This parameter can be changed by adding the following line to the /etc/system file: 'set ufs_ninode = 5295'. NOTE: Don't forget to check /etc/system first to see if there's already a set command modifying this tunable parameter. If there is, modify that command instead of adding another one. Once this change has been implemented, changes to the maxusers parameter will no longer affect ufs_ninode.

We do not recommend implementing all of these changes at once. More information on how to change tunable parameters is available in the System Administration Guide. We recommend making a copy of /etc/system before making changes, and understanding how to use boot -a in case your changes to /etc/system create an unbootable system.