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Date:   Thu, 4 Feb 2021 10:54:57 +0000
From:   Andy Smith <andy@strugglers.net>
To:     linux-btrfs@vger.kernel.org
Cc:     linux-raid@vger.kernel.org
Subject: Re: put 2 hard drives in mdadm raid 1 and detect bitrot like btrfs
 does, what's that called?
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Hi Cedric,

On Wed, Feb 03, 2021 at 08:33:18PM +0100,   wrote:
> it's called "dm-integrity", as mentioned in this e-mail:
> https://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg93037.html

If you do this it would be very interesting to see performance
figures for the following setups:

- btrfs with raid1 meta and data allocation
- mdadm raid1 on raw devices
- mdadm raid1 on dm-integrity (no encryption) on raw devices
- mdadm raid1 on dm-integrity (encryption) on raw devices

just to see what kind of performance loss dm-integrity and
encryption is going to impose.

After doing it, it would find a nice home on the Linux RAID wiki:

    https://raid.wiki.kernel.org/index.php/Dm-integrity

Cheers,
Andy