> ZeroFS supports running multiple instances on the same storage backend: one read-write instance and multiple read-only instances.

Well that's a big limiting factor that needs to be at the front in any distributed filesystem comparison.

Though I'm confused, the page says things like "ZeroFS makes S3 behave like a regular block device", but in that case how do read-only instances mount it without constantly getting their state corrupted out from under them? Is that implicitly talking about the NBD access, and the other access modes have logic to handle that?

Edit: What I want to see is a ZeroFS versus s3backer comparison.

Edit 2: changed the question at the end