On Fri, Mar 15, 2024 at 10:05:16AM -0400, Phillip Susi wrote: > Dave Chinner <david@xxxxxxxxxxxxx> writes: > > > How do other filesystems behave? Is this a problem just on specific > > filesystems? > > I finally got around to testing other filesystems and surprisingly, it > seems this is only a problem for ext4. That's what I expected - I would have been surprised if you found problems across multiple filesystems... > I tried btrfs, f2fs, jfs, udf, > and xfs. xfs even uses the same jbd2 for journaling that ext4 does > doesn't it? .... because none of them share "journalling" code at all. They all have their own independent mechanisms for ensuring data and metadata integrity. ext4/jbd2 actually shares little code with other Linux filesystems - ocfs2 is the only other linux filesystem that uses jbd2. > I just formatted a clean fs, synced, and ran blktrace, then synced > again, and only ext4 emits a flush on the second sync. So this really sounds like it's just a bug in ext4/jbd2 behaviour and so there's no real general filesystem or infrastructure problem that needs to be fixed here.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
