I regularly install and try lots of free, open source software applications. One of my better recent finds is a customizable system monitor utility called GKrellM.  Like many open source applications, its name is puzzling, but it is a useful and very customizable way to monitor processes and components on Mac, Windows and Linux systems. Lifehacker and MakeUseOf originally alerted me to the large ecosystem of plugins that you can use to customize GKrellM, which made me want to try it.

GKrellM started life as a Linux application, but you’ll find download options for the Mac and Windows at the bottom of this page. When installing on Windows, you’ll see the application’s Linux roots at work in a list of files that represent components in the application, similar to how package components are listed for Linux applications. You actually just need to download the program’s installer .EXE file, though, and it will take care of the whole setup.

The application presents you with a stack of separately monitored processes and components on your computer. It offers all the essential system monitoring applets, including a CPU monitor, a disk monitor, an Internet monitor that displays TCP port connections, file system meters, a memory meter, and much more. The memory meter, for example, could be particularly useful for people working on netbooks or other systems with limited hardware resources.

GKrellM is most differentiated from other system monitors, though, by its plugins. There are many really creative examples to be found on the plugins page. You can get a plugin for periodically updating your desktop wallpaper, including a timer that will execute the next change. There are also plugins for showing the time in multiple timezones, and an organizer plug-in for tracking to-do list items. Just as open source applications such as Firefox get their appeal from useful collections of extensions, GKrellM benefits from a user community that contributes free plugins.

GKrellM sits on your desktop as it monitors processes, but it is a polite application. You can shut it down at any time by right-clicking on it and selecting “Quit.” It’s worth a try, especially if you’re working with limited system resources.

What’s your favorite GKrellM plugin?

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