5 ms·

> we're further along than btrfs in "will it keep my data" Honestly Kent, this continuing baseless fearmongering from you about btrfs is absolutely disgusting.

> we're further along than btrfs in "will it keep my data" Honestly Kent, this continuing baseless fearmongering from you about btrfs is absolutely disgusting. It costs you. I was initially very interested in bcachefs, but I will never spend my time testing it or contributing to it as long as you continue behave this way. I'm certain there are many many others who would nominally be very interested, but feel the same way I do. Your filesystem charitably gets 0.001% the real world testing btrfs does. To claim it is more reliable than btrfs is ignorant and naive. Maybe it actually is more reliable in the real world (press X to doubt...), but you can't possibly know yet, and you won't know for a long time.

rob_c 1y ago
I'm happy to support that bcache may have a stable on disk format, but the lashing out at the alternatives is another example of behaviour I'd prefer to see dropped. If your product is so great its it's own advert. If it has problems spend the limited person power fixing it not attacking the opposition, this is what ciq have done, do better.
koverstreet 1y ago
We have documented, in this very thread, issues with multi device setups that btrfs has that bcachefs does not - and btrfs developers ignoring these issues. This isn't baseless fearmongering, this is "did you think through the failure modes when you were designing the basics". This stuff comes up over, and over, and over. Engineering things right matters, and part of that absolutely is comparing and documenting approaches and solutions to see what went right and what went wrong. This isn't a popularity contest, and this isn't high school where we form into cliques and start slinging insults. Come up with facts, documentation, analysis. That's what we do. I'm tired of these threads degenerating into flamewars.
- kzrdude 1y ago
  (That's impressive, but the real world user pool is much smaller isn't. It still sounds like a proud brag more than it does proven by workload.) I am not a filesystems guy, but I was disappointed when I realized that btrfs did not have a good design for ENOSPC handling. So I'm curious, does bcachefs design for a benign failure mode when out of space?
  - koverstreet 1y ago
    We have enough user reports of multi device testing that they put both bcachefs and btrfs through, where bcachefs consistently survives where btrfs does not. We have much better repair and recovery, with real defense in depth. Now: I am not saying that bcachefs is yet trouble free enough for widespread deployment, we're still seeing cases where repair needs fairly minor work, but the filesystem may be offline while we get that fixed. OTOH we also recover, regularly, from absolutely crazy scenarios involving hardware failure: flaky controllers, lightning strikes, I've seen cases where it looked like a head crashed - took out a whole bunch of btree nodes in similar LBA ranges. IOW: the fundamentals are very solid, but keep checking back if you're wondering when it'll be ready for widespread deployment. Milestones to watch for: - 3 months with zero data loss or downtime events: I think we may get this soon, knock on wood - stable backports starting: 6.17, knock on wood (or maybe we'll be out of the kernel and coming up with our own plan, who knows) - weird application specific bugs squashed: these have been on the back burner, but there's some weird stuff to get to still (e.g. weird unlink behavior that affects docker and go builds, and the Rust people just reported something odd when building certain packages with mold). And yes, we've always handled -ENOSPC gracefully.
    - motorest 1y ago
      > We have enough user reports of multi device testing that they put both bcachefs and btrfs through, where bcachefs consistently survives where btrfs does not. We have much better repair and recovery, with real defense in depth. Are any of these claims verifiable, or even made by anyone other than yourself? Frankly, without substantiating any claim or even providing any concrete evidence, it reads like trying to badmouth what you perceive as competitors in a desperate attempt to get some traction. Not cool.
      - koverstreet 1y ago
        There's a lot of user feedback out there, try the mailing lists.
        1y ago
Dylan16807 1y ago
I haven't lost data on btrfs but I have broken half the partitions I made with it. The comparison doesn't feel baseless to me. > 0.001% the real world testing Statistics can be quite powerful. If you have a million installs, and your billion-install competitor has 100 problems per million installs, you can make some pretty strong statements about how you rate against that competitor. Just for easy example numbers.
pmarreck 1y ago
I've bricked 2 drives to btrfs (one on Manjaro and one on Arch), and 0 to bcachefs. Of course, I've never used bcachefs as a daily driver... nor as a filesystem in general... but I'd love to... lol

rob_c 1y ago

I'm happy to support that bcache may have a stable on disk format, but the lashing out at the alternatives is another example of behaviour I'd prefer to see dropped. If your product is so great its it's own advert. If it has problems spend the limited person power fixing it not attacking the opposition, this is what ciq have done, do better.

koverstreet 1y ago

We have documented, in this very thread, issues with multi device setups that btrfs has that bcachefs does not - and btrfs developers ignoring these issues. This isn't baseless fearmongering, this is "did you think through the failure modes when you were designing the basics". This stuff comes up over, and over, and over. Engineering things right matters, and part of that absolutely is comparing and documenting approaches and solutions to see what went right and what went wrong. This isn't a popularity contest, and this isn't high school where we form into cliques and start slinging insults. Come up with facts, documentation, analysis. That's what we do. I'm tired of these threads degenerating into flamewars.

kzrdude 1y ago
(That's impressive, but the real world user pool is much smaller isn't. It still sounds like a proud brag more than it does proven by workload.) I am not a filesystems guy, but I was disappointed when I realized that btrfs did not have a good design for ENOSPC handling. So I'm curious, does bcachefs design for a benign failure mode when out of space?
- koverstreet 1y ago
  We have enough user reports of multi device testing that they put both bcachefs and btrfs through, where bcachefs consistently survives where btrfs does not. We have much better repair and recovery, with real defense in depth. Now: I am not saying that bcachefs is yet trouble free enough for widespread deployment, we're still seeing cases where repair needs fairly minor work, but the filesystem may be offline while we get that fixed. OTOH we also recover, regularly, from absolutely crazy scenarios involving hardware failure: flaky controllers, lightning strikes, I've seen cases where it looked like a head crashed - took out a whole bunch of btree nodes in similar LBA ranges. IOW: the fundamentals are very solid, but keep checking back if you're wondering when it'll be ready for widespread deployment. Milestones to watch for: - 3 months with zero data loss or downtime events: I think we may get this soon, knock on wood - stable backports starting: 6.17, knock on wood (or maybe we'll be out of the kernel and coming up with our own plan, who knows) - weird application specific bugs squashed: these have been on the back burner, but there's some weird stuff to get to still (e.g. weird unlink behavior that affects docker and go builds, and the Rust people just reported something odd when building certain packages with mold). And yes, we've always handled -ENOSPC gracefully.
  - motorest 1y ago
    > We have enough user reports of multi device testing that they put both bcachefs and btrfs through, where bcachefs consistently survives where btrfs does not. We have much better repair and recovery, with real defense in depth. Are any of these claims verifiable, or even made by anyone other than yourself? Frankly, without substantiating any claim or even providing any concrete evidence, it reads like trying to badmouth what you perceive as competitors in a desperate attempt to get some traction. Not cool.
    - koverstreet 1y ago
      There's a lot of user feedback out there, try the mailing lists.
      - 1y ago

Dylan16807 1y ago

I haven't lost data on btrfs but I have broken half the partitions I made with it. The comparison doesn't feel baseless to me. > 0.001% the real world testing Statistics can be quite powerful. If you have a million installs, and your billion-install competitor has 100 problems per million installs, you can make some pretty strong statements about how you rate against that competitor. Just for easy example numbers.

pmarreck 1y ago

I've bricked 2 drives to btrfs (one on Manjaro and one on Arch), and 0 to bcachefs. Of course, I've never used bcachefs as a daily driver... nor as a filesystem in general... but I'd love to... lol