Online GC stage 2: Track dangling blobs and manifests
Problem to solve
As documented in the specification, the second stage of online GC is to track dangling blobs and manifests.
Besides tracking blob associations (#254 (closed)), we also need to track dissociations to detect potentially dangling blobs in the deduplicated storage. A blob that is no longer referenced in a particular repository may be referenced in another one. However, the database is scoped and partitioned by repository, which means that each repository must take care of flagging potentially dangling blobs internally.
Proposal
Implement the second stage of online GC as described in the specification.
Edited by João Pereira