[XYen0n]

You are correct; I confused archiving with compression. However, even considering only the compression process, same compression parameters cannot be guaranteed, as it is unknown which compression parameters the image publisher used.

[flakes]

Thats true. And regardless of compressed vs regular tar, I think the OCI format working with opaque archives is extremely limiting. I hope the industry will eventually redesign to use content addressable storage per file and have metadata to describe the layer/disk layout instead. That would allow per file deduplication, and we can use tar for just bulk transfer over the wire, rather than using tar for the data at rest.

[cpuguy83]

containerd 2.3 has support for erofs which does a direct import of the layer. It can even convert the tar based layers to erofs, faster than extracting the tar normally.

Also looking at block-based content store so that blocks can be deduped across images.