←back to thread

Bcachefs Goes to "Externally Maintained"

(lwn.net)
214 points ksec | 5 comments | 30 Aug 25 13:07 UTC | HN request time: 0.013s | source
Show context
LeoPanthera ◴[30 Aug 25 17:28 UTC] No.45076431[source]▶
It's orphaned in Debian as well, but I'm not sure what significant advantages it has over btrfs, which is very stable these days.
replies(1): >>45076586 #
betaby ◴[30 Aug 25 17:47 UTC] No.45076586[source]▶
btrfs was unusable in multi disk setup for kernels 6.1 and older. Didn't try since then. How's stable btrs today in such setups?

Also see https://www.phoronix.com/news/Josef-Bacik-Leaves-Meta

replies(5): >>45076637 #>>45076834 #>>45076978 #>>45076998 #>>45081574 #
LeoPanthera ◴[30 Aug 25 17:52 UTC] No.45076637[source]▶
It's sort of frustrating that this constantly comes up. It's true that btrfs does have issues with RAID-5 and RAID-6 configurations, but this is frequently used (not necessarily by you) as some kind of gotcha as to why you shouldn't use it at all. That's insane. I promise that disk spanning issues won't affect your use of it on your tiny ThinkPad SSD.

It's important to note that striping and mirroring works just fine. It's only the 5/6 modes that are unstable: https://btrfs.readthedocs.io/en/stable/Status.html#block-gro...

replies(5): >>45076707 #>>45076727 #>>45076740 #>>45076809 #>>45077208 #
1. betaby ◴[30 Aug 25 18:02 UTC] No.45076740[source]▶
But RAID-6 is the closest approximation to raid-z2 from ZFS! And raid-z2 is stable for a decade+. Indeed btrfs works just fine on my laptop. My point is that Linux lacks ZFS-like fs for large multi disc setups.
replies(1): >>45076800 #
2. NewJazz ◴[30 Aug 25 18:09 UTC] No.45076800[source]▶
Seriously for the people who take filesystems seriously and have strong preferences... Multi disk might be important.
replies(1): >>45077429 #
3. wtallis ◴[30 Aug 25 19:42 UTC] No.45077429[source]▶
BTRFS does have stable, usable multi-disk support. The RAID 0, 1, and 10 modes are fine. I've been using BTRFS RAID1 for over a decade and across numerous disk failures. It's by far the best solution for building a durable array on my home server stuffed full of a random assortment of disks—ZFS will never have the flexibility to be useful with mismatched capacities like this. It's only the parity RAID modes that BTRFS lacks, and that's a real disadvantage but is hardly the whole story.
replies(1): >>45083148 #
4. Filligree ◴[31 Aug 25 13:51 UTC] No.45083148{3}[source]▶
That’s nice and all, but I have five disks in my server. I want the 6 mode.

In practice RAIDZ2 works great.

replies(1): >>45089687 #
5. wtallis ◴[01 Sep 25 05:18 UTC] No.45089687{4}[source]▶
In the case of five disks of the same capacity, RAID6 or RAIDZ2 only gets you 20% more capacity than btrfs RAID1. That's not exactly a huge disparity, usually not enough to be a show-stopper on its own. There are plenty of scenarios where the features ZFS has which btrfs lacks are more important than the features that btrfs has which ZFS lacks. My point is simply that btrfs RAID1 has its uses and shouldn't be dismissed out of hand.