Many months ago when a web application running in Tomcat on a Linux
server experienced intermittent and severe performance problems I
setup a cron task to record Tomcat free memory and operating system
load average. I plotted these figures on a chart using JFreeChart and
I was able to get huge insight into the problem which other tools
failed to provide.
I'd like to expand this script to record other potentially useful data
which I can use as a baseline should problems arise in future.
Besides load average and tomcat free memory -- what else should I
record given that I'm running a pretty typical Java/Linux/Tomcat/MySQL
server. The kind items that come to mind is network IO, disk IO, page
fault rate.... BTW: what's the best way of getting the page fault
rate? I can't find the right file in /proc for that.