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From:   Phillip Susi <phill@thesusis.net>
To:     Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Cc:     Andrei Borzenkov <arvidjaar@gmail.com>,
        Jan Ziak <0xe2.0x9a.0x9b@gmail.com>,
        linux-btrfs@vger.kernel.org
Subject: Re: Btrfs autodefrag wrote 5TB in one day to a 0.5TB SSD without a
 measurable benefit
Date:   Thu, 17 Mar 2022 16:34:51 -0400
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Zygo Blaxell <ce3g8jdj@umail.furryterror.org> writes:

> You can get a 1-byte file reference if you make a reflink of the last
> block of a 4097-byte file, or punch a hole in the first 4096 bytes of a
> 4097-byte file.  This creates a file containing only a reference to the
> last byte of the original extent.

So the inode only refers to one byte of the extent, but the extent is
still always a multiple of 4k right?