Running multiple applications in one docker container

Question

This question is part of my continuing exploration of Docker and in some ways follows up on one of my earlier questions. I have now understood how one can get a full applic

Answer 1

@Bryan's answer is solid, particularly in relation to the overheads of a container that just runs one process being low.

That said, you should at least read the arguments at https://phusion.github.io/baseimage-docker/, which makes a case for having containers with multiple processes. Without them, docker is light on provision for:

• process supervision
• cron jobs
• syslog

baseimage-docker runs an init process which fires up a few processes besides the main one in the container.

For some purposes this is a good idea, but also be aware that for instance having a cron daemon and a syslog daemon per container adds up a bit more overhead. I expect that as the docker ecosystem matures we'll see better solutions that don't require this.