Docker's aufs diff folder is growing huge in terms of size
I had same issue and the spotify/docker-gc fixed it. Clone it then follow "Running as a Docker Image"
The spotify/docker-gc is not going to fix it, but it make things to turn for the better much easier. The first thing you need to do is to stop doing commits on the same image. As I've realized, this is going to build up a huge diff-dependency. What I did is that I've committed all my running containers into different image names and tags, stopped and restarted the containers. After that, I've deleted the old images manually, then ran spotify/docker-gc. I've saved about 20% of disk space. If I ran spotify/docker-gc before the commits into new images, nothing happened.
If you use spotify/docker-gc, please do DRY_RUN.