There are quite a number of ways to look at running processes on Linux systems – to see what’s running, the resources that processes are using, how the system is affected by the load and how memory is being used. Each command gives you a different view, and the range of details is considerable. In this post, we’ll run through a series of commands that can help you view process details in a number of different ways.
While the ps command is the most obvious command for examining processes, the arguments that you use when running ps will make a big difference in how much information will be provided. With no arguments, ps will only show processes associated with your current login session. Add a -u and you'll see extended details.
Thanks to Sandra Henry-Stocker (see source)