Comment on Best Filesystem for NAS?

• Eideen@lemmy.world ⁨4⁩ ⁨months⁩ ago

  Yes both BTRFS and Ext4 are vulnerable to unplanned powerloss when writes are in flight. Commonly knows as a write hole.

  For BTRFS since it use of Copy of Write, it is more vulnerable. As metadata needs to be updated and more. Ext4 does not have CoW.

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  • Atemu@lemmy.ml ⁨4⁩ ⁨months⁩ ago

    Ext4 does not have CoW.

    That’s the only true part of this comment.

    As for everything else:

    Ext4 uses journaling to ensure consistency.

    btrfs’ CoW makes it resistant to that issue by its nature; writes go elsewhere anyways, so you can delay the “commit” until everything is truly written and only then update the metadata (using a similar scheme again).

    Please read en.wikipedia.org/wiki/Journaling_file_system.

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    • Eideen@lemmy.world ⁨4⁩ ⁨months⁩ ago

      BTRFS is currently not Journaling

      lore.kernel.org/linux-btrfs/…/T/#m46f1e018485e6cb…

      Qu Wenruo did a write up on some of the edge cases. Partial write being one of them.

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      • Atemu@lemmy.ml ⁨4⁩ ⁨months⁩ ago

        What you just posted concerns the experimental RAID5/6 mode which, unlike all other block group modes, did not have CoW’s inherent safety.

        As it stands, there is no stable RAID5/6 support in btrfs. If we’re talking about non-experimental usage of btrfs, it is irrelevant.

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  • TCB13@lemmy.world ⁨4⁩ ⁨months⁩ ago

    For BTRFS since it use of Copy of Write, it is more vulnerable. As metadata needs to be updated and more. Ext4 does not have CoW.

    This is where theory and practice diverge and I bet a lot of people here will essentially have the same experience I have. I will never run an Ext filesystem again, not ever. BTRFS, ZFS, XFS all far superior and more reliable.

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    • Eideen@lemmy.world ⁨4⁩ ⁨months⁩ ago

      I run BTRFS my self.

      And I agree BTRFS , is superior.

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• Cyber@feddit.uk ⁨4⁩ ⁨months⁩ ago

  Never had an issue with EXT4.

  Had a problem on a NAS where BTRFS was taking “too long” for systemD to check it, so just didn’t mount it… bit of config tweaking and all is well again.

  I use EXT* and BTRFS where ever I can because I can manipulate it with standard tools (inc gparted).

  I have 1 LVM system which was interesting, but I wouldn’t do it that way in the future (used to add drives on a media PC)

  And as for ZFS … I’d say it’s very similar to BTRFS, but just slightly too complex on Linux with all the licensing issues, etc. so I just can’t be bothered with it.

  As a throw-away comment, I’d say ZFS is used by TrusNAS (not a problem, just sayin’…) and… that’s about it??

  As to the OPs original question, I agree with the others here… something’s not right there, but it’s probably not the filesystem.

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