This is a particularly good monitoring tool to install. Let it run for at least a full day, and at the end of a day, run sar -A | less You will be amazed at how many system resources are being monitored. Also, it is an "old school" tool from the commercial UNIX world, and has earned the respect of many gray-bearded admins. Finally, O'Reilly's "Swordfish book", System Performance Tuning, gives a great explanation on what useful data you can get from sar, and what it is trying to tell you about the system health. The book is a bit dated now, but there's still plenty of great stuff in there. Nice to see someone pushing this tool, as it is usually one of the first packages I install after a clean build. Also check out http://www-128.ibm.com/developerworks/eserver/library/es-unix-perfmonsar.html