The performance of Linux desktop environments is normally described in the order XFCE, GNOME, KDE – in decreasing order. Interesting in this case is that almost no one can point the finger to recent comparisons or real figures – mostly it is just a blur mix of rumors and only few personal experiences.
Lubos Lunak tried to shed a bit of light on this topic and made some comparisons of start up times and memory performance of different desktop setups. Keep in mind with these results that the start up times are made with a bit older versions of both desktops. Even the memory consumption research was not done with GNOME 2.16 because it was just released – you have to make the cut somewhere.
The results speak for themselves: GNOME eats much, much more memory than KDE. Still, XFCE uses less memory. However, if you add applications the effect that KDE preloads some base libraries shows it advantages: the applications are more lightweight. Therefore the desktop together with a set of libraries is much less memory eating than GNOME. Even XFCE comes into trouble when you add bigger apps.
But, keep in mind that such tests are quite difficult to perform – the author gives a couple of reasons why for example the tool “Free” cannot be used to measure the memory consumption accurate enough, and he also discusses the results quite detailed.
However the basic message is plain clear: KDE as a memory eating desktop environment is a Myth, nothing more. It compares better against XFCE as GNOME, and when you load a set of applications additional, KDE performs better and better in comparison.
Also, nice too see but not surprising is that OpenOffice is a more memory. That’s one of its biggest flaws, I thing, that it actually eats more memory than the entire KDE desktop! (I would like to see how many memory MS Office in Wine would need compared to OpenOffice.Org.).
So, for the next discussion there are now real figures available – together with a quite good analysis. This will hopefully clear some rants and rumours (and minds) to come back to normal discussions and friendly competition between the desktops.