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Date:   Thu, 7 Jul 2022 06:36:46 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Christoph Hellwig <hch@infradead.org>, Qu Wenruo <wqu@suse.com>,
        linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 00/12] btrfs: introduce write-intent bitmaps for RAID56
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On Thu, Jul 07, 2022 at 01:48:11PM +0800, Qu Wenruo wrote:
> - It may not support RAID56 for metadata forever.
>   This may not be a big deal though.

Does parity raid for metadata make much sense to start with?

> - Not yet determined how RST to handle non-COW RAID56 writes

The whole point is that with parity raid you really do not ever want
to do non-COW writes, as that is what gets you the raid hole problem.