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From:   Phillip Susi <phill@thesusis.net>
To:     Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc:     linux-btrfs@vger.kernel.org
Subject: Re: [PATCH v5 00/13] btrfs: introduce RAID stripe tree
Date:   Thu, 09 Feb 2023 10:57:00 -0500
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Johannes Thumshirn <johannes.thumshirn@wdc.com> writes:

> A design document can be found here:
> https://docs.google.com/document/d/1Iui_jMidCd4MVBNSSLXRfO7p5KmvnoQL/edit?usp=sharing&ouid=103609947580185458266&rtpof=true&sd=true

Nice document, but I'm still not quite sure I understand the problem.
As long as both disks have the same zone layout, and the raid chunk is
aligned to the start of a zone, then shouldn't they be appended together
and have a deterministic layout?

If so, then is this additional metadata just needed in the case where
the disks *don't* have the same zone layout?

If so, then is this an optional feature that would only be enabled when
the disks don't have the same zone layout?