Andrew Pruski explains why docker kill is so much faster than docker stop:
When running demos and experimenting with containers I always clear down my environment. It’s good practice to leave a clean environment once you’ve finished working.
To do this I blow all my containers away, usually by running the docker stop command.
But there’s a quicker way to stop containers, the docker kill command.
Sending SIGTERM isn’t particularly polite and doesn’t let processes clean up, which could leave your process in an undesirable state during future runs. But if you’re just re-deploying a container, you don’t really care about the prior state of the now-disposed container.