GEFS on OpenBSD: A Early Preview

sippingabonedry

GEFS: A Good Enough File System https://orib.dev/gefs.pdf

dchest

Talk at EuroBSDCon 2026: https://exquisite.tube/w/3QQimMdswWJxrsPaJtak2u

g0xA52A2A

There was a recent presentation on this at EuroBSDCon for those interested. https://events.eurobsdcon.org/2026/talk/NVMSCJ/ https://exquisite.tube/w/3QQimMdswWJxrsPaJtak2u

doublepg23

This is great timing considering I'm currently dealing with FFS corruption after my OpenBSD server lost power during a storm.

metalforever

Finally . Very good work team !

anthk

Ori B. it's a great programmer, he fixed a small bug on the earlier GeFS on 9front versions in no time. It worked fine in my n270 based Atom netbook under 9front, so it will run perfectly well under OpenBSD in a near future. It isn't as resource heavy as ZFS, and it will be more reliable than FFS, for sure.

geoffbp

> The git repo is hidden on shithub Heh :)

moody__

I've been following (and helping test) gefs on 9front for a while now. 9front's nightly builder has been running off of it for quite a while. Ori's done a fantastic job.

yjftsjthsd-h

From https://orib.dev/gefs.pdf - > While snapshot consistency is useful to keep data consistent, disks often fail over time. In order to detect corruption, block pointers contain a hash of the data that they point at. If corrupted data is returned by the underlying storage medium, this is detected via block hashes. And if a programmer error causes the file system to write garbage to disk, this can often be caught early. The corruption is reported, and the damaged data may then be recovered from backups, RAID restoration, or some other means. Okay! It's got CoW, snapshots, and data checksums. Therefore, it's good enough to compete with ZFS while being way smaller and permissively licensed. Now I just want it ported to Linux and the other BSDs:)

fn-mote

Is there any chance of proving a filesystem is correct? Is this one simple enough that it won’t have bugs?? Given the issues with well-known filesystems like ZFS and BetterFS, why shouldn’t I expect data-losing bugs in this one?

calvinmorrison

I have been running GEFS for a number of days and it hasnt crashed 248 ├gefs [ctl.1] 249 ├gefs [mutate.2] 250 ├gefs [sweep.3] 251 ├gefs [tasks.-1] 252 ├gefs [readio.4] 253 ├gefs [syncio.5] 254 ├gefs [srvio.-1] 255 ├gefs [stdio.-1] up 13 days, 15:34:25 send it to production!!

BoingBoomTschak

What a wonderful surprise! The nearest thing seem to be modern (v5) XFS + dm-integrity, I'll have to see a comparison once it's stable enough. A thing ZFS suffers from is fragmentation (no way to defragment in-place nor preallocate so stuff like bittorrent doesn't play well with it), which it justifies with its CoW design, wonder if/how it mitigates the problem.

ThePowerOfFuet

>Error handling is largely commented out. First we do the first 90%, and then we do the last 90%.

throw0101a

From NYC*BUG† May 2023, "GEFS, A Good Enough File System" By Ori Bernstein: * https://www.youtube.com/watch?v=juFndFy72gI September 2026 EuroBSDCon presentation from Sunday: * https://www.youtube.com/watch?v=yPoU4QEv_u8&t=49m43s † BSD User Group

tiffanyh

All respect to the author on their work, but for me personally - I'm be more interested in Hammer2 (from Dragonfly BSD) to come to OpenBSD. https://github.com/kusumi/openbsd_hammer2

jijji

> Error handling is largely commented out. I guess we won't really know when the file system breaks or corrupts data

limagnolia

I've always wondered why HAMMER2 from DragonFlyBSD hasn't gotten more attention from other OSes?