Linux memory is calculated using Available memory instead of Used memory

[dmacbale-cas]

Going to run some commands inside of a container to demonstrate the issue here. I'm also going to use free -m instead of free -b because it's easier to see differences.

$ free -m
              total        used        free      shared  buff/cache   available
Mem:           7951         578        4292         333        3080        6919
Swap:          1024           0        1024

{print $2} should match total:

$ free -m | grep "Mem:" | awk '{print $2}'
7951

Looks good!

{print $7} should match used:

$ free -m | grep "Mem:" | awk '{print $7}'
6919

It matches available.

[dmacbale-cas]

I can't make a pull request but if you change line 43:
https://github.com/sydcanem/node-free/blob/master/index.js#L43

From:

    return parseInt(exec('free -b | grep "Mem:" | awk \'{print $7}\'', {'encoding' : 'utf8'}), 10);

to:

    return parseInt(exec('free -b | grep "Mem:" | awk \'{print $3}\'', {'encoding' : 'utf8'}), 10);

That should do the trick!