It is important not only to "spot-check" system performance with the tools mentioned above, but to collect longer-term performance histories so you can detect trends. If nothing else, a baseline record of a system performing well will help you figure out what has changed if the system starts behaving poorly. Enable the system activity reporting package by doing the following:
Edit the file /etc/init.d/perf and remove the # comment characters from the lines near the end of the file. For Solaris 10, run the following command:
svcadm enable system/sar
Run the command crontab -e sys and remove the # comment characters from the lines with the sa1 and sa2 commands. You can adjust how often the commands run and at what times of day depending on your site's activity profile. See the crontab man page for an explanation of the format of this file.
This command causes the system to store performance data in files in the /var/adm/sa directory, where by default they are retained for one month. You can then use the sar command to examine the statistics for time periods of interest.