Why the system information message when accessing an Ubuntu server doesn't match free -m?
- by Andres
Each time I SSH into my AWS Ubuntu servers I see a system information message, showing load, memory usage and packages available to install, like this:
Welcome to Ubuntu 12.04.3 LTS (GNU/Linux 3.2.0-51-virtual x86_64)
* Documentation: https://help.ubuntu.com/
System information as of Sun Nov 10 18:06:43 EST 2013
System load: 0.08 Processes: 127
Usage of /: 4.9% of 98.43GB Users logged in: 1
Memory usage: 69% IP address for eth0: 10.236.136.233
Swap usage: 100%
Graph this data and manage this system at https://landscape.canonical.com/
13 packages can be updated.
0 updates are security updates.
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*** /dev/xvda1 will be checked for errors at next reboot ***
*** System restart required ***
My question is about the memory percentage shown. In this case, it's showing a 69% of memory usage, but since the swap usage was 100% I checked it by myself. So when I run free -m I get this:
total used free shared buffers cached
Mem: 1652 1635 17 0 4 29
-/+ buffers/cache: 1601 51
Swap: 895 895 0
And that's of course closer to 100% than to 69%