How to delete build cache (buildkit experimental)

General
1

When using the experimental docker buildkit features: https://github.com/moby/buildkit/blob/master/frontend/dockerfile/docs/experimental.md

Specifically: RUN --mount=type=cache,target=/root/mycache ....

How do I clean up (delete) this cache mount when I want to trigger a fresh build?
I would assume there would be a command similar to “docker volume rm” but the cache mounts don’t
appear in docker volume ls.

2

docker builder prune --filter type=exec.cachemount

3

Thanks @tonistiigi this works great.

I used a different filter to target a specific id: docker builder prune --filter id=......

Is there a way to give the cache a name so that I can more easily target it? The documentation says that there is an optional ID I can pass but when I do:

RUN --mount=id=my-project-cache,type=cache,target=/path/to/dir nothing changes, that is when using docker system df -v the cache id is still a random string.

4

Is it possible to get a reply here @tonistiigi? It’s still a problem in 2023.

5

@tonistiigi It looks like someone may be taking this on?