On Tue, Aug 12, 2025 at 11:24:18AM +0200, Johannes Thumshirn wrote: > On Mon, Aug 11, 2025 at 12:08:12PM -0400, Kent Overstreet wrote: > > I think bcachefs has been a bit of a kick in the pants for them, they've > > taken some stuff directly from bcachefs - e.g. I believe they took the > > basic design of raid5 v2, the stripes tree, directly from bcachefs. A > > btrfs engineer asked me and I explained the design at a conference some > > years back [...] > > Just one single mail and I will not reply to any follow ups on this. But I > feel the need to clarify things as people have approached me. Yes Kent and I > have talked about RAID. This has been at LSFMM 2024 in Salt Lake City. > > I can't remember if we talked about stripe trees, I only remember us talking > about erasure coding, which Kent has done for bcachefs and I was planning to > do for btrfs as well. > > But the 1st presentations I did on the idea of the stripe tree have been Lund > Linux Conference and Plumbers in 2022 [1]. This is easy to look up. In the > beginning the RAID stripe tree didn't have anything to do with RAID5 and the > write hole at all (this is just a nice side effect) but with doing RAID on > zoned block devices and ZONE APPEND writing. > > [1] https://lpc.events/event/16/contributions/1235/attachments/1111/2132/BTRFS%20RAID-DP.pdf Thanks for the correction :)
