Shuttle XS29f: Linux Looks Great in Green (LinuxPlanet)

There are a lot of shared libraries used in Gnome. So how Linux deals with that is that it loads up the libraries once in ram and then that portion of ram is re-used for multiple applicaitons.

The RSS size is what it would be if you were to use that particular application in a completely stand-alone manner. (which isn't really accurate either since most programs depend on something like gnome-keyring or whatever to work properly).

So if you were to try to run gnome-panel in KDE with no other gnome stuff then that it would really use up that 30MB of RAM. But in Gnome at least 1/3 of the application is shared among other applications so the overal memory usage will be much less then it originally seems.

This is why you will see relatively low real-world games by using a 'lite' system like XFCE over Gnome. Even though XFCE avoids gnome libs applications still tend to need the same sort of functionality and instead of using shared libraries they invent that functionality on their own. So depending on your applications you can actually end up using MORE resources in a 'lite' environment rather then just sticking with Gnome and using pure gnome* stuff.

*Of course pure gnome stuff is rarely used. Ubuntu, Fedora, et al ship with configurations that use a lot of non-gnome stuff like OpenOffice.org or Firefox, which duplicate a hell of a lot of the functionality provided by gnome/gtk libraries. With the simple addition of those two programs, running simultanously, you will effectively double the memory requirements of your desktop.