1.1 KiB
What Garbage Collection Does
Garbage collection is a process that delete blobs to which no manifests refer. It runs in two phases. First, in the 'mark' phase, the process scans all the manifests in the registry. From these manifests, it constructs a set of content address digests. This set is the 'mark set' and denotes the set of blobs to not delete. Secondly, in the 'sweep' phase, the process scans all the blobs and if a blob's content address digest is not in the mark set, the process will delete it.
How to Run
You can run garbage collection by running
docker run --rm registry-image-name garbage-collect /etc/docker/registry/config.yml
NOTE: You should ensure that the registry itself is in read-only mode or not running at all. If you were to upload an image while garbage collection is running, there is the risk that the image's layers will be mistakenly deleted, leading to a corrupted image.