gcrane-gc

List untagged images

$ gcrane gc [repository]

$ gcrane gc [repository] [[-r|--recursive]]

$ gcrane gc [[-h|--help]]

gcrane gc [--dry-run] [--quiet] [--parallelism=N] repository

--dry-run
    Simulate deletion; print layers that would be removed without action

--quiet
    Suppress all non-error output

--parallelism=N
    Number of parallel workers (default: 10)

gcrane-gc (or gcrane gc) is a subcommand of the gcrane tool for managing Google Container Registry (GCR) repositories. It performs garbage collection by identifying and deleting container image layers that are no longer referenced by any manifests, thereby reclaiming storage space.

This command is essential for repository maintenance, as Docker layers can accumulate over time from deleted tags or images, leading to wasted quota. It scans the specified repository, computes layer references via manifests, and removes dangling blobs.

Usage requires Google Cloud authentication via gcloud auth. It operates only on gcr.io repositories and supports dry-run mode for safe testing. Parallelism can be tuned for large repos. Note that gcrane is deprecated in favor of modern tools like crane and Artifact Registry.

Requires gcloud auth login; deprecated tool—migrate to Artifact Registry; deletes layers irreversibly outside dry-run; limited to gcr.io repos.

Run gcloud auth configure-docker and gcloud auth login first.

gcrane gc --dry-run gcr.io/my-project/my-repo
Tests deletion of unreferenced layers.

Introduced by Google ~2017 for GCR management; deprecated post-2021 with Artifact Registry launch, urging migration to crane.

crane(1), gcloud(1), docker(1)