gkrellm and top give VERY different ram stats.

[kuber]

I have 512m ram.

top says I have 132 free
gkrellm says I have 441 free

huh?

[demetrius]

I believe gkrellm reports used RAM based on RAM that is currently used by running proccesses, whereas top reports used RAM based on RAM used by current proccesses+cached RAM, which is not actually 'used' RAM per se as it can be freed as needed. The more accurate reading is the one reported by gkrellm as far as I know.

[kuber]

Cool-thanks for the help, I was a bit worried there that I had some sort of leak or something.

[Strike]

GKrellM is more "right" in the way you are probably thinking of memory usage.

Like demetrius said, it reports memory currently being used by processes. The other 441MB can be used by any program that needs it right away. But, 309MB of that has "leftover" stuff in it from when programs were running earlier and needed it. But, who is Linux to say that it won't use that memory again? As such, it doesn't really clear out the memory - it still has the info in it, but it is marked as "free-able" since it isn't in immediate use. So, if all of the "clean" memory (with nothing in it) becomes used, it starts overwriting the "free"-able memory.

[optech]

what is the console command to show the ACTUAL free memory? (memory not in use... not the leftovers)

[Strike]

My one-liner to do so is:

free -m | grep s/c | awk '{print $4}'

That's how many MB you have not in immediate use.

Or you can just do free -m and look at the second row, the second number column:

[ddipaolo@half-life ddipaolo]$ free -m

total used free shared buffers cached
Mem: 250 189 60 0 18 88
-/+ buffers/cache: 83 166
Swap: 243 0 243
For example, I have 166 MB free. My one-liner returns:

[ddipaolo@half-life ddipaolo]$ free -m | grep s/c | awk '{print $4}'
166