While I've never had any problems with slowdowns on my Linux system because of this, this issue always confused me.
I'm running SuSe 10.1, KDE 3.5.1, on a 3GHz Intel CPU, with 1GB of memory (+ 4GB of swap memory).
aMule (currently doing nothing)
OpenOffice.org (3 documents)
I'm the only user currently logged in.
And yet, the top command gives the following:
Mem: 1033888k total, 1009584k used, 24304k free, 82544k buffers
Swap: 4088500k total, 40k used, 4088460k free, 403656k cached
Where does the full 1GB of memory usage comes from? If this is right, I shouldn't be able to, say, play a video--which I know I can. So why does this say I'm using all this memory, and if I'm not really, how do I find out how much I'm really using?