What Is Registry Garbage Collection?

Registry garbage collection is the process a container registry uses to delete layers and manifests that are no longer referenced by any tag. Untagging an image does not immediately free space because shared layers may still be in use; garbage collection later removes blobs with no remaining references. It keeps registry storage from growing unbounded.

Why it matters

CI that pushes an image per commit accumulates enormous layer storage fast, and most of it is dead within days. A retention policy plus garbage collection caps that growth and its cost. Because layers are shared, deleting a tag is safe; only truly unreferenced blobs are collected.

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