From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xavier Nicollet <nicollet@jeru.org>
Subject: Re: Balance RAID10 with odd device count
Date: Wed, 22 Feb 2012 09:56:27 +0100
Message-ID: <20120222085627.GS30450@jeru.org>
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To: Hugo Mills <hugo@carfax.org.uk>, tom@drdabbles.us,
	Gareth Pye <gareth@cerberos.id.au>, linux-btrfs@vger.kernel.org
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Le 21 February 2012 ? 07:54, Hugo Mills a =E9crit:
>    Some time ago, I proposed the following scheme:
>=20
> <n>C<m>S<p>P
>=20
>    where n is the number of copies (suffixed by C), m is the number o=
f
> stripes for that data (suffixed by S), and p is the number of parity
> blocks (suffixed by P). Values of zero are omitted.
>=20
>    So btrfs's RAID-1 would be 2C, RAID-0 would be 1CnS, RAID-5 would
> be 1CnS1P, and RAID-6 would be 1CnS2P. DUP would need a special
> indicator to show that it wasn't redundant in the face of a whole-dis=
k
> failure: 2CN

Seems clear. However, is the S really relevant ?
It would be simpler without it, wouldn't it ?

--=20
Xavier Nicollet
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