You can also remove dead containers with this command
docker rm $(docker ps --all -q -f status=dead)
But, I’m really not sure why & how the dead containers are created. This error seems related https://github.com/typesafehub/mesos-spark-integration-tests/issues/34 whenever i get dead containers
[Update]
With Docker 1.13 update, we can easily remove both unwanted containers, dangling images
$ docker system df #will show used space, similar to the unix tool df
$ docker system prune # will remove all unused data.