From mboxrd@z Thu Jan  1 00:00:00 1970
From: NeilBrown <neilb@suse.de>
Subject: Re: Guess the size of a RAID{5,6} device
Date: Sat, 12 Apr 2014 09:50:49 +1000
Message-ID: <20140412095049.6cce32a6@notabene.brown>
References: <5347A58B.2060308@gmail.com>
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To: Francis Moreau <francis.moro@gmail.com>
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On Fri, 11 Apr 2014 10:19:23 +0200 Francis Moreau <francis.moro@gmail.com>
wrote:

> Hello,
>=20
> I'd like to know if it's possible to get the size of a RAID{5,6} which
> is not created yet but the size of the partitions which will make up the
> array are.

How precise does the "guess" need to be?

If you subtract about 128Meg from the size of the partitions, round down the
a multiple of the chunk size then multiply by the number of data disks, you
should come quite close.

If you want an exact number, then you really need to create the array.

NeilBrown


>=20
> Thanks
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