Memory Usage on Linux box does not match up with `free`

Posted by Chris Lieb on Server Fault See other posts from Server Fault or by Chris Lieb
Published on 2010-05-19T21:15:10Z Indexed on 2010/05/19 21:20 UTC
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Filed under:

linux

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memory

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memory-usage

I have a Linux machine that is not running too much in the way of software, but is somehow using 1.7GB of the 2GB of the installed memory. When I run free, I get:

             total       used       free     shared    buffers     cached
Mem:       2072616    1979972      92644          0     164876     129740
-/+ buffers/cache:    1685356     387260
Swap:       498004       1632     496372

However, when I run ps aux, the memory usage of all processes only comes out to 295.9MB, which is a far cry from the 1.7GB of memory that free reports as used.

Why is there such a discrepancy?

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