6 Nov 2015

Linux Commands to Find Total and Free RAM

Looking to find how much primary memory (RAM) a Linux box has got? I have two ways of doing this.

The first is using the free command.

[testuser@testbox ~]$ free
             total       used       free     shared    buffers     cached
Mem:       1921908     432344    1489564        168      47820     254852
-/+ buffers/cache:     129672    1792236
Swap:      2097148          0    2097148

The second is to use the /proc virtual file system. This displays the values in Kilobytes which might be more user-friendly to some

[test@testbox ~]$ more /proc/meminfo | grep ^Mem
MemTotal:        1921908 kB
MemFree:         1489548 kB

I prefer the first when I want to just look at the info and move on. And I tend to go for the second when I need to have this info available for shell scripts, etc.

I am sure there are loads of other ways to do this. Have one you prefer? Please share it - along with why you think it works better for you.

Also, the commands above provide loads more information than just free and used memory. Do take a minute to look through their man pages below for future reference.

More Info: manual pages for free and proc(5)