What about other filesystems?

Posted Jan 18, 2021 10:29 UTC (Mon) by farnz (subscriber, #17727)
In reply to: What about other filesystems? by Wol
Parent article: Fast commits for ext4

No, because even on ancient systems, you had elevator reordering for performance, and no guarantees about metadata writes; in the event of a crash, you simply did not know the state of the update or the transaction log, as even if you wrote them in a careful order, the elevator could reorder writes to disk, and the metadata writes might be reordered, too.

In other words, as soon as there's a kernel panic or a power failure, all bets are off on an old UNIX system. This wasn't an issue with reliable systems, but as reliability went down (no dedicated power supplies, no UPSes etc), it became an issue again.