An update on bcachefs

One thing to point out about slow btrfs scrubs is that it depends on your IO scheduler. Use the standard CFQ or BFQ. If you use deadline or noop then of course the scrub is going to use up all the IO because nothing will stop it.

It still causes some extra latency. On my email server I use multi-queue BFQ and I can feel a bit of extra delay when loading each IMAP message from it during a scrub, but I don't think it's that serious.

And on my laptop with NVMe SSD the btrfs scrub is done in about 30 seconds, so it isn't a big deal there either. It reads and verifies at hundreds of megabytes per second.