I like to keep on top of my machines health. I like to do this without programs getting in my way, or dedicating desktop space to monitoring applications. The way I’ve found to do this simply and effectively is with the System Monitor panel Applet.
Adding the System Monitor Applet
To add the system monitor applet to one of your panels (I prefer the top panel), simply right-click and select “Add to Panel”. Scroll down until you see “System Monitor: A system load indicator”. Select it and select Add. You should now have a small black box on your panel which will monitor cpu activity.
I like to take this one step further and also monitor memory, network, load average, swap and disk activity. This can be done by right-clicking on the new applet and selecting “Preferences”. At the top of this preferences window you have the options of activating the resources you wish to monitor. I check all of these boxes.
As you check each one you’ll get an additional box in your panel. Each one monitors something different and in a different color (customizable). You can now, at a glance, see the cpu load, network usage and all the rest without running any additional applications.
I find this to be a quick, efficient and out-of-the-way method of monitoring my machine.