Visualizing SAR’s data

When you build a server architecture for a project, your often want to test the performance afterwards. That’s true especially when the only way to know the application needs is to test them.

Most distributions  already come with the needed tools to measure your performance of the operating system with tools like top, free, vmstat, iostat, mpstat and sar. The latter is usually configured to run periodically through cron to collect statistics all the time.

But when you want to analyze the data, creating a graph is much better way to do it. I found two ways to do that easily:

1. Using kSar, which reads the sar files and lets you choose which graph to show. As this is a java application its platform independent and can be using everywhere.
2. Using sar2rrd and RRDTool.

I used the first method as it lets the user creates the graphs with a GUI, and makes my life easier. kSar also support creating a PDF report from the raw data, and thus lets the user/me to send an easy report for others to review.

If you need to follow graphs for many systems over time, I would advise you to install Cacti, which collects the data and summarize it nicely with a web intreface.