Where did my memory go? linux box

Question

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.

possible duplicate of [Why does Red Hat Linux report less free memory on the system than is actually available?](http://serverfault.com/questions/9442/why-does-red-hat-linux-report-less-free-memory-on-the-system-than-is-actually-ava) — Warner, Jul 09 '10 at 22:50

score 3 · Accepted Answer · answered Jul 09 '10 at 22:50

3

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

answered Jul 09 '10 at 22:50

Warner

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So i am using 95mb and have 397 cached? -/+ buffers/cache: 95 397 – Jul 09 '10 at 22:53
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397 would be the free amount if I'm reading what you're attempting to say correctly. See also: http://www.linuxatemyram.com/ – Warner Jul 09 '10 at 22:54

score 1 · Answer 2 · answered Jul 09 '10 at 22:51

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

answered Jul 09 '10 at 22:51

runlevelsix

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"sar" is another good command too. – Raffael Luthiger Jul 10 '10 at 00:27
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 02:42

score 0 · Answer 3 · answered Jul 09 '10 at 22:48

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try this

top -d 0.5

and if you want post the output

answered Jul 09 '10 at 22:48

DimitrisD

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Where did my memory go? linux box

3 Answers3