Hi! Until yesterday, I've been using Kubuntu with 512MB of RAM. The RAM usage was always about the 98% and linux rarely used the swap partition (except when I ran VMWare), so I went for some more RAM. I bought another 512MB module (DDR1), and just for a while, I borrowed 1GB from my brother and 256MB from my mother, summing 2304MB... So I started opening all the programs I could, Amarok playing music, VLC playing an AVI, OpenOffice, VMWare, etc. But my CPU usage was 100% and the playing video started skipping before I could use all the RAM.
The strange thing is that, as I closed everything, the RAM usage kept going up to a 98% and the swap usage was of about 30-40MB. And still 10 or 20 minutes after this, the RAM usage didn't drop.
Now, with 1GB of RAM the same thing happens. Just some minutes after power on, and having only opened a couple of programs (let's say Firefox and Konqueror) the RAM usage starts increasing until almost the whole RAM is taken and again 30-40mb from swap are used.

Maybe this is normal in the memory management scheme of linux, but just in case, I wanted to ask.
I'm using Beryl with XGL, SuperKaramba and VMWare (with 256MB of RAM) sometimes. The CPU is a P4 Prescott 2.4Ghz.
Is there any output that could be useful? Like the memory usage per process (non-virtual, right?), which I couldn't find how to display.
Thanks in advance, and greetz!

Yes it is.

try top (total of processes, I believe)

for processes you could also try ksysguard as your running KDE

yes, that sounds like a good one. And I just found top isn't total of processes, it is top of CPU processes ---- guess I am acronym-oriented

Thanks for all the responses. The RES field in top seems to be the same as the VmRss in ksysguard, ie. the amount of physical memory currently used by a process (not including shared libraries and swaped out pages). So, the sum of those fields should be the 'used mem' reported by 'free', right?
Then I don't understand why either having 512, 1024 or 2304 MB of RAM, the whole amount is used... any idea?

As stated, this is the way Linux mm is designed - what's the point of paying for memory, then having it laying around unused ???.
Have a look at this (ignore the gentoo specific bits).

The reason you're seeing 98% memory usage is because, instead of letting unused memory go to waste, Linux apportions free memory for disk caching purposes. Which means that if an app wants something off disk, the cache is checked first. It provides a (small) performance boost. As for swap.. this can be adjusted via the kernel 'swappiness' option. Even if you've got lots of RAM, if 'swappiness' is set quite high, then unused memory will get swapped out to disk to make room for other apps. There's plenty of information available on the web covering this... but if your system runs nicely as-is, you might as well leave it...

Thanks kevinatkins for the info!
So there's not invisible process eating my RAM...
And syg00 I'll go through that page as soon as I can, before taking Understanding The Linux Kernel out of my shelf and resuming it Bye!