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by scaladev 1888 days ago
The other way to interpret this would be "it was the only filesystem to detect corruption on my malfunctioning hardware", because that's what usually happens in the last few years.

Or have you been using ZFS on the same hardware?
2 comments
yjftsjthsd-h 1887 days ago
I haven't used ZFS on the same hardware, but during the time when BTRFS ate itself multiple times my home partition on the same drive also on BTRFS was perfectly fine, so it'd have to be an awfully specific hardware failure. Also, it would have had to hit the metadata both times since we're talking "pool wouldn't import" not "it gave me data checksum errors". Which again, is possible, but on an SSD with wear-leveling seems a tad unlikely.
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NavinF 1888 days ago
He said "corrupt its root filesystem beyond repair", not "detect checksum errors"

Btw raid5/6 is still broken on btrfs which makes it a hard sell for any system with more than 2 disks. cf. raidz on ZFS

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scaladev 1888 days ago
So? Do you think filesystem metadata is stored in a magical pixie cloud, or on the same unreliable physical hardware where it can easily get corrupted, especially after a crash or an unexpected power loss?

I posted this link here already:

https://www.usenix.org/conference/atc19/presentation/jaffer

f2fs (at least in its state a couple of years ago) is/was a prime example of how a filesystem can get into a barely working state with massive amounts of data and metadata corruption, and not even notice it.

God I love this site. In case of a minor disagreement with someone don't even bother to think, just press "downvote".

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fomine3 1888 days ago
Corrupt data should be corrected by checksummed btrfs, isn't it?
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CorrectHorseBat 1888 days ago
Only if you have more than one copy of the data
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KozmoNau7 1888 days ago
RAID 5 has been generally advised against for years, due to performance issues and the effect of unrecoverable errors during rebuilds.

Btrfs RAID1 works perfectly, and RAID1c3/RAID1c4 provides additional redundancy. In place of RAID5, use RAID10 instead.

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NavinF 1888 days ago
raidz2 is only advised against if your arrays are so small that you don't care about the price of storage.

If you want more IOPS, add more raidz2 (raid6) stripes to the pool. In practice, spinning rust is the new tape. Trying to do random access under 1MB is just silly

I don't stress over rebuilds. 2 more disks failing during a rebuild is incredibly unlikely compared to everything else that might force me to restore a backup (software bugs, data center flooding, etc).

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