Cleaning Up & Resource Limits

Prune safely

Images, stopped containers and build cache pile up. prune removes unused ones.

docker system df            # see disk usage
docker container prune       # remove stopped containers
docker image prune -a        # remove unused images
docker system prune --volumes  # careful: also removes unused volumes

Limit resources

Limits stop one container from starving the host.

docker run -d --name api --memory 512m --cpus 1.5 --restart unless-stopped my-app:1.0

prune --volumes can delete database data. Read the confirmation prompt, and prefer named volumes for anything you cannot afford to lose.