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From: Phillip Susi <phill@thesusis.net>
To: Dave Chinner <david@fromorbit.com>
Cc: linux-fsdevel@vger.kernel.org, Theodore Ts'o <tytso@mit.edu>
Subject: Re: Uneccesary flushes waking up suspended disks
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 <Ze5fOTojI+BhgXOW@dread.disaster.area>
Date: Fri, 15 Mar 2024 10:05:16 -0400
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Dave Chinner <david@fromorbit.com> 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.  I tried btrfs, f2fs, jfs, udf,
and xfs.  xfs even uses the same jbd2 for journaling that ext4 does
doesn't it?

I just formatted a clean fs, synced, and ran blktrace, then synced
again, and only ext4 emits a flush on the second sync.