In much of the hype around containers I often hear statements such as:
Linux containers are very lightweight...you can potentially run thousands of them on a single server...
I understand that by definition containers share the kernel of the underlying OS and that the containers themselves (the container daemons) are lightweight but it's not as if someone is going to fire up a thousand empty containers. There'll be database processes, web servers, jobs of all types running inside the containers and these all have whatever are their typical memory/working set requirements. So how is the statement about being able to run thousands of containers a practical consideration?