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Comment by sippingabonedry | Hacker News Reader

> I dropped btrfs after the second time it hosed my rootfs

btrfs fans use the "you're using it wrong" excuse a lot.

I recall a failure mode that activated when you fill the FS to 100% and their response was "you should never fill a filesystem to capacity"

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They also fucked up their parity RAID repair so that the next disk failure on a different disk will destroy the data, argued that the pathological B-tree performance reported by a user couldn't be real, because they didn't understood the tree depth would only be logarithmic to the base of the fanout if the entries are the same size. insert shocked pikachu face

That failure mode is still there although it's been mitigated a bit. I hit it a few months ago but was able to recover after a few hours of doing various stuff.

Yeah that's not how filesystems are supposed to work.

You should be able to dd /dev/zero to a file and not worry about the entire filesystem shitting the bed.

It's really a shame, though. btrfs is permanently unfinished, and zfs has the wrong license. End result is people stick with ext4 or xfs most of the time anyway.

Otoh, good luck bringing a CoW filesystem back from 100%. Delete a file? Sure, let me just make a copy of all the metadata that was pointing at it using... the zero blocks I have left.

Tradeoffs are a bitch, bitch.

Which is why ZFS reserves "slop space" to make sure that doesn't happen, instead of defaulting to making it easy for users to corner themselves like that.

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