Memory Usage
On linux, there are commands for almost everything, because the gui might not be always available. When working on servers only shell access is available and everything has to be done from these commands. So today we shall be checking the commands that can be used to check memory usage on a linux system. Memory include RAM and swap.
It is often important to check memory usage and memory used per process on servers so that resources do not fall short and users are able to access the server. For example a website. If you are running a webserver, then the server must have enough memory to serve the visitors to the site. If not, the site would become very slow or even go down when there is a traffic spike, simply because memory would fall short. Its just like what happens on your desktop PC.
1. free command
The free command is the most simple and easy to use command to check memory usage on linux. Here is a quick example
$ free -m
total used free shared buffers cached
Mem: 7976 6459 1517 0 865 2248
-/+ buffers/cache: 3344 4631
Swap: 1951 0 1951
