The previous post describes a problem where you do a large docker build, then fan out to many jobs which need to pull this image, and the overhead is enormous. This implies rwx has less overhead. Just saying that there’s content addressable cache doesn’t explain how this particular problem is solved.

If you have a dockerfile where you make a small change in your source results in one particular very large layer that has to be built, then you want to fan out and run many parallel tests using that image, what actually happens when you try to run that new fat layer on a bunch of compute, and how is it better than the implied naive solution? That fat layer exists on a storage system somewhere, and a bunch of computer nodes need to read it, what happens?