Kent has admitted (many times) that snapshots are one of the more difficult features to add in a reliable and safe way, and will require significant work to do right, especially for what he wants to see them do (I assume "really damn fast and low overhead" is a major one, plus some other tricks he has up his sleeve.) So he has intentionally not tackled them yet, instead going after a slew of other features first. Reflink, full checksum, replication, caching, compression, native encryption, etc. All of that works today.
Snapshots are a huge feature for sure, but it's not like bcachefs is completely incapable without them.
There was a very recent update he gave in late December (2019) that mentioned he's actively chipping away at the roadblocks for snapshots.
They're being worked on ATM:
Dec 29, 2019
"Just finished a major rework that gets us a step closer to snapshots: the btree code is incrementally being changed to handle extents like regular keys."
https://www.patreon.com/posts/towards-32698961
Heh, BTRFS deja vu. Been hearing about the ZFS alternative "not quite there, but catching up" for about as long as high-speed rail. I wonder which will arrive first :)
aseipp|6 years ago
Snapshots are a huge feature for sure, but it's not like bcachefs is completely incapable without them.
There was a very recent update he gave in late December (2019) that mentioned he's actively chipping away at the roadblocks for snapshots.
ZoomZoomZoom|6 years ago
fgonzag|6 years ago
Rapzid|6 years ago