Comment on Best Filesystem for NAS?
Eideen@lemmy.world 9 months agoYes 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.
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.
I run BTRFS my self.
And I agree BTRFS , is superior.
Atemu@lemmy.ml 9 months ago
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.
Eideen@lemmy.world 9 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.
Atemu@lemmy.ml 9 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.