5 ms·

How the heck did this ever make it through? I don't think this ever would have happened pre-OpenZFS, and undermines the stable reputation of ZFS. OpenZFS needs

by davisr 3y ago

How the heck did this ever make it through? I don't think this ever would have happened pre-OpenZFS, and undermines the stable reputation of ZFS. OpenZFS needs to do better and look to FreeBSD developers, not Linux developers, as role models.

deleted 3y ago
[deleted]
ryao 3y ago
A FreeBSD developer wrote this code.
- keep_reading 3y ago
  So far nobody has proven that this bug exists on FreeBSD, though. :)
  - Always_Anon 3y ago
    Because FreeBSD is behind Linux in copying with reflinks. They couldn't even reproduce the issue if they wanted to.
    - ryao 3y ago
      This code was implemented for FreeBSD before it was implemented for Linux. I do not think it has made it to a FreeBSD release yet though.
      - Always_Anon 3y ago
        No it wasn't: https://github.com/openzfs/zfs/issues/405 https://github.com/openzfs/zfs/issues/405 This hit Linux first, which is why Linux experienced the issue. FreeBSD does not currently have reflink cp.
      - mnd999 3y ago
        It’s in FreeBSD 14. But they disabled block cloning by default.
        deleted 3y ago
        [deleted]
  - ryao 3y ago
    The bugs are in cross platform code beneath the VFS. They exist on FreeBSD too.
  - frankjr 3y ago
    https://github.com/openzfs/zfs/issues/15526#issuecomment-1823682717 https://github.com/openzfs/zfs/issues/15526#issuecomment-182...
    - keep_reading 3y ago
      Looks like a deeper bug has been exposed due to the way bclone works? They're finding issues now on ZFS versions predating bclone Edit: yep, it's an older bug. Set zfs_dmu_offset_next_sync=0 to save your data https://github.com/openzfs/zfs/issues/15526#issuecomment-1823760920 https://github.com/openzfs/zfs/issues/15526#issuecomment-182...
      - frankjr 3y ago
        Not sure what's your point. The comment I linked to just confirmed that the bug (whichever it might be) has reproduced on FreeBSD.
        keep_reading 3y ago
        Just following up for the readers of the thread
      - fortani 3y ago
        Nope, somebody managed to reproduce this issue even with zfs_dmu_offset_next_sync=0 https://github.com/openzfs/zfs/issues/15526#issuecomment-1826065538 https://github.com/openzfs/zfs/issues/15526#issuecomment-182...
        keep_reading 3y ago
        Apply this patch, it appears to be the real fix. https://github.com/openzfs/zfs/pull/15571/files?diff=split&w=0 https://github.com/openzfs/zfs/pull/15571/files?diff=split&w...
- gonzo 3y ago
  and then there were deep concerns about the stability of same, so vfs.zfs.bclone_enabled = 0 was left in-place https://github.com/freebsd/freebsd-src/commit/068913e4ba3dd9b3067056e832cefc5ed264b5cc https://github.com/freebsd/freebsd-src/commit/068913e4ba3dd9...
uberduper 3y ago
I'm reading through the bug report and the investigation in the comments. Is there something here that makes this bug extremely obvious to you that nobody else is comprehending?
Always_Anon 3y ago
>How the heck did this ever make it through? Because it was introduced by a FreeBSD developer, and FreeBSD's fs and cp are a generation behind Linux's so they weren't even able to hit this. >I don't think this ever would have happened pre-OpenZFS, and undermines the stable reputation of ZFS. Of course it happened pre-OpenZFS: https://blog.lastinfirstout.net/2010/04/bit-by-bug-data-loss-running-oracle-on.html?m=1 https://blog.lastinfirstout.net/2010/04/bit-by-bug-data-loss... From the people that brought you Slowlaris. >OpenZFS needs to do better and look to FreeBSD developers, not Linux developers, as role models. This was introduced by a FreeBSD developer and was caught by a Linux one. You need to rethink your role models.
- aforwardslash 3y ago
  >Because it was introduced by a FreeBSD developer, and FreeBSD's fs and cp are a generation behind Linux's This is often regarded as a good thing in the BSD world. In all fairness, this bug just enforces that notion. And Solaris (at least on amd64) wasn't slow. It was demanding, and not really suited for desktop. And it was picky with hardware. Totally agree on the rest of your comment, though.
  - Always_Anon 3y ago
    >This is often regarded as a good thing in the BSD world. In all fairness, this bug just enforces that notion. Same in Linux, which is why you'd choose a distro that's less bleeding edge. >And Solaris (at least on amd64) wasn't slow. No, it was slow. There's a reason why everyone in HPC/HFT/etc. moved off Solaris to Linux in the 2000s. Linux was regularly beating Slowlaris in practically every category at the end.
- Squossifrage 3y ago
  [flagged]
- ryao 3y ago
  >Because it was introduced by a FreeBSD developer, and FreeBSD's fs and cp are a generation behind Linux's so they weren't even able to hit this. Honestly, this feature could have used more testing on both platforms. Also, FreeBSD's VFS in theoretically able to support reflinks across datasets while Linux's VFS disallows that. It is not really behind.
WD40ForRust2 3y ago
It seems like a meme that GPL software developers are more ego driven than BSD/MIT software developers, and so bike shedding and new features take precedence over correctness/simplicity/beauty. I was a decade long Gentoo user who was frustrated by crashy software, switched back to pirated windows (I would never be caught dead paying for windows), only to find out the same trash developer habits carried over in my absence and now windows sucks just as much plus IT SPIES ON YOU!!! I'm now on Qubes OS hoping Xen is well enough built to assuage my anxieties.
- ryao 3y ago
  The Linux developers involved use the CDDL. While some of them have patches in Linus’ tree, most of them are described as Linux developers because they develop and use the code on Linux. They have little to do with mainline Linux, partly because certain the mainline Linux developers will actively go out of their way to antagonize them if they even try to contribute to mainline. Certain others will simply ignore their emails. I will not say names, but I have had that happen to me in the past. That said, I suspect you did not read the replies, since the code in question was written by a FreeBSD developer. Bugs in new code have been introduced by developers on both platforms. Unfortunately, the bugs in this feature were not caught before they reached a stable release. :/
- doublepg23 3y ago
  > bike shedding and new features take precedence over correctness/simplicity/beauty. I just learned the recent FreeBSD 14 release doesn't have 802.11n WiFi support. Is that considered bike shedding?
SirMaster 3y ago
You don't have to enable all these fancy new features in your zpools even if you update your build of zfs if you don't want to. I have multiple zpools and none of them have been upgraded to enable any of these new features in the past couple years.
- ryao 3y ago
  That alone probably protected a number of users from hitting this.

by davisr 3y ago

deleted 3y ago

[deleted]

ryao 3y ago

A FreeBSD developer wrote this code.

keep_reading 3y ago
So far nobody has proven that this bug exists on FreeBSD, though. :)
- Always_Anon 3y ago
  Because FreeBSD is behind Linux in copying with reflinks. They couldn't even reproduce the issue if they wanted to.
  - ryao 3y ago
    This code was implemented for FreeBSD before it was implemented for Linux. I do not think it has made it to a FreeBSD release yet though.
    - Always_Anon 3y ago
      No it wasn't: https://github.com/openzfs/zfs/issues/405 https://github.com/openzfs/zfs/issues/405 This hit Linux first, which is why Linux experienced the issue. FreeBSD does not currently have reflink cp.
    - mnd999 3y ago
      It’s in FreeBSD 14. But they disabled block cloning by default.
      - deleted 3y ago
        [deleted]
- ryao 3y ago
  The bugs are in cross platform code beneath the VFS. They exist on FreeBSD too.
- frankjr 3y ago
  https://github.com/openzfs/zfs/issues/15526#issuecomment-1823682717 https://github.com/openzfs/zfs/issues/15526#issuecomment-182...
  - keep_reading 3y ago
    Looks like a deeper bug has been exposed due to the way bclone works? They're finding issues now on ZFS versions predating bclone Edit: yep, it's an older bug. Set zfs_dmu_offset_next_sync=0 to save your data https://github.com/openzfs/zfs/issues/15526#issuecomment-1823760920 https://github.com/openzfs/zfs/issues/15526#issuecomment-182...
    - frankjr 3y ago
      Not sure what's your point. The comment I linked to just confirmed that the bug (whichever it might be) has reproduced on FreeBSD.
      - keep_reading 3y ago
        Just following up for the readers of the thread
    - fortani 3y ago
      Nope, somebody managed to reproduce this issue even with zfs_dmu_offset_next_sync=0 https://github.com/openzfs/zfs/issues/15526#issuecomment-1826065538 https://github.com/openzfs/zfs/issues/15526#issuecomment-182...
      - keep_reading 3y ago
        Apply this patch, it appears to be the real fix. https://github.com/openzfs/zfs/pull/15571/files?diff=split&w=0 https://github.com/openzfs/zfs/pull/15571/files?diff=split&w...
gonzo 3y ago
and then there were deep concerns about the stability of same, so vfs.zfs.bclone_enabled = 0 was left in-place https://github.com/freebsd/freebsd-src/commit/068913e4ba3dd9b3067056e832cefc5ed264b5cc https://github.com/freebsd/freebsd-src/commit/068913e4ba3dd9...

uberduper 3y ago

I'm reading through the bug report and the investigation in the comments. Is there something here that makes this bug extremely obvious to you that nobody else is comprehending?

Always_Anon 3y ago

>How the heck did this ever make it through? Because it was introduced by a FreeBSD developer, and FreeBSD's fs and cp are a generation behind Linux's so they weren't even able to hit this. >I don't think this ever would have happened pre-OpenZFS, and undermines the stable reputation of ZFS. Of course it happened pre-OpenZFS: https://blog.lastinfirstout.net/2010/04/bit-by-bug-data-loss-running-oracle-on.html?m=1 https://blog.lastinfirstout.net/2010/04/bit-by-bug-data-loss... From the people that brought you Slowlaris. >OpenZFS needs to do better and look to FreeBSD developers, not Linux developers, as role models. This was introduced by a FreeBSD developer and was caught by a Linux one. You need to rethink your role models.

aforwardslash 3y ago
>Because it was introduced by a FreeBSD developer, and FreeBSD's fs and cp are a generation behind Linux's This is often regarded as a good thing in the BSD world. In all fairness, this bug just enforces that notion. And Solaris (at least on amd64) wasn't slow. It was demanding, and not really suited for desktop. And it was picky with hardware. Totally agree on the rest of your comment, though.
- Always_Anon 3y ago
  >This is often regarded as a good thing in the BSD world. In all fairness, this bug just enforces that notion. Same in Linux, which is why you'd choose a distro that's less bleeding edge. >And Solaris (at least on amd64) wasn't slow. No, it was slow. There's a reason why everyone in HPC/HFT/etc. moved off Solaris to Linux in the 2000s. Linux was regularly beating Slowlaris in practically every category at the end.
Squossifrage 3y ago
[flagged]
ryao 3y ago
>Because it was introduced by a FreeBSD developer, and FreeBSD's fs and cp are a generation behind Linux's so they weren't even able to hit this. Honestly, this feature could have used more testing on both platforms. Also, FreeBSD's VFS in theoretically able to support reflinks across datasets while Linux's VFS disallows that. It is not really behind.

WD40ForRust2 3y ago

It seems like a meme that GPL software developers are more ego driven than BSD/MIT software developers, and so bike shedding and new features take precedence over correctness/simplicity/beauty. I was a decade long Gentoo user who was frustrated by crashy software, switched back to pirated windows (I would never be caught dead paying for windows), only to find out the same trash developer habits carried over in my absence and now windows sucks just as much plus IT SPIES ON YOU!!! I'm now on Qubes OS hoping Xen is well enough built to assuage my anxieties.

ryao 3y ago
The Linux developers involved use the CDDL. While some of them have patches in Linus’ tree, most of them are described as Linux developers because they develop and use the code on Linux. They have little to do with mainline Linux, partly because certain the mainline Linux developers will actively go out of their way to antagonize them if they even try to contribute to mainline. Certain others will simply ignore their emails. I will not say names, but I have had that happen to me in the past. That said, I suspect you did not read the replies, since the code in question was written by a FreeBSD developer. Bugs in new code have been introduced by developers on both platforms. Unfortunately, the bugs in this feature were not caught before they reached a stable release. :/
doublepg23 3y ago
> bike shedding and new features take precedence over correctness/simplicity/beauty. I just learned the recent FreeBSD 14 release doesn't have 802.11n WiFi support. Is that considered bike shedding?

SirMaster 3y ago

You don't have to enable all these fancy new features in your zpools even if you update your build of zfs if you don't want to. I have multiple zpools and none of them have been upgraded to enable any of these new features in the past couple years.

ryao 3y ago
That alone probably protected a number of users from hitting this.