Mastodawn

which is "better", XFS or BTRFS? i only care about file system resilience on shitty SSDs, so like, which one is going to be slower at letting my photos be randomly destroyed by bit flips? #linux

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>>>>>>>1d ago

@aeva filesystems are kind of an emotional topic i feel like, temper your expectations of results accordingly.

my personal opinion: ext4 and xfs do not store checksums of file data, only metadata. btrfs and zfs store checksums of the file data itself too. so btrfs and zfs will detect bit flips in the file data, while ext4 and xfs will not. because of this i prefer btrfs and zfs

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aeva 23h ago

@artemis I'm hearing conflicting reports on the checksumming thing

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>>>>>>>23h ago

@aeva I'm poking around the xfs code to see if i can find anything conclusive, but unfortunately filesystems are big so no guarantees

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>>>>>>>

@aeva The define for the CRC feature bit says

#define XFS_FEAT_CRC (1ULL << 13) /* metadata CRCs */

I've found a lot of CRCing code and it does seem to be conditional on that feature, but none of it seems to directly contradict this comment saying it's specifically metadata. It has the thing I was afraid of though where there's so much bookkeeping code that it's hard to find the actual path a file write takes and what's happening to the data of the write vs the metadata around the write. Tapping out for now.