Correctly determining memory usage in Linux
I see that almost all my RAM is in use. Is this bad? Strange thing is I don't see what is actually using the RAM.
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No problem in that. Linux is borrowing the RAM for caching. This is desirable (RAM is faster than disk) and absolutely normal behaviour.
From that link:
To see how much RAM you have free, type
Thus I'm using about 1.5 GB RAM, not 4 GB as the first line might make it look like.
Its mostly linux caching data. If you use