Certain Docker images (rhel in this case) cause the _uploads folder to contain data that is never erased.
Steps to reproduce:
Note: The below was tested on Docker client 1.12, but is reproducible on 1.10 as well. In 1.9 an empty _uploads folder is created but no data is placed in it.
1. docker pull rhel (this is pulled from a legacy V1 repository)
2. docker tag rhel <url-to-docker-repo>/my-rhel:latest
3. docker push <url-to-docker-repo>/my-rhel:latest
After the image is finished being pushed, a layer (which actually contains JSON data rather than binary) is leftover in the _uploads folder. The image itself still functions and is able to be pulled/used.
If this image is used in other images, this would require a lot of manual cleanup to remove these layers.