I'm really not a linux master, so the question might sound a bit silly.

andscape-sysinfo displays: "Memory usage: 45% "
and free -m outputs:
total used free
Mem: 1000 779 221

meaning that 221 out of 1000 is free (22.1% is free or 80% usage)

Which parameter should I believe in ?

Thanks

Some of your 'not free' RAM is probably being used for caching. Does the output of your free command give you any more info? Here's what mine looks like:

# free -m
             total       used       free     shared    buffers     cached
Mem:          4039       3827        212          0        221       3150
-/+ buffers/cache:        455       3584
Swap:          511          0        511

I know it doesn't look like I have much free RAM, but the memory allocated to caching will be released if/when necessary.

You can also take a look at the memory info from the 'top' command. It should tell you if you have RAM allocated to caching or buffers.


MSJ

Thank you, never knew about caching

See here http://www.linuxatemyram.com/

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