RAM Raiders - Where has my RAM gone ?

Looking at my Linux box ( I am running Red Hat Enterprise Linux Server release 6.4 ), I was wondering where my RAM had gone .....

This is what I have: -

free -m

             total       used       free     shared    buffers     cached
Mem:         16081       8876       7205          0        378       7036
-/+ buffers/cache:       1462      14619
Swap:         8015        153       7862

Don't worry, this site had the answer: -

http://www.linuxatemyram.com/

<snip>

How do I see how much free ram I really have?

To see how much ram is free to use for your applications, run free -m and look at the row that says "-/+ buffers/cache" in the column that says "free". That is your answer in megabytes:

$ free -m

             total       used       free     shared    buffers     cached

Mem:          1504       1491         13          0         91        764

-/+ buffers/cache:        635        

869

Swap:         2047          6       2041

$

If you don't know how to read the numbers, you'll think the ram is 99% full when it's really just 42%.

</snip>

In other words, I have most of my 16 GB RAM available to me ( ~89% ) which is nice.