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I just got a linux box and i installed apache, mono and i'm about to install mysql.

I checked the memory with free -mt and got this.

             total       used       free     shared    buffers     cached
Mem:           492        470         22          0         31        343

This means i have 492mb in total and i am using 470!?! how can i be using 470! i should only be running apache2. How do i figure out where my ram is going.

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I am sure its NOT reporting memory falsely. – acidzombie24 Jul 9 '10 at 22:52
up vote 5 down vote accepted

The -/+ buffers/cache displays the actual memory available on the free column. Linux uses unused memory for caching disk I/O.

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So i am using 95mb and have 397 cached? -/+ buffers/cache: 95 397 – acidzombie24 Jul 9 '10 at 22:53
397 would be the free amount if I'm reading what you're attempting to say correctly. See also: – Warner Jul 9 '10 at 22:54

Use top and/or vmstat for further analysis of memory and memory usage in Linux.

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"sar" is another good command too. – Raffael Luthiger Jul 10 '10 at 0:27
dstat FTW. 'dstat -af' has never failed to give me a good idea of what is going on in the system. That is, if my terminal is wide enough. – Slartibartfast Jul 10 '10 at 2:42

try this

top -d 0.5

and if you want post the output

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