From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andy Smith <andy@lug.org.uk>
Subject: Re: Mustn't be RAID 1 and 0 read-performance be similar?
Date: Thu, 9 Aug 2007 14:13:10 +0000
Message-ID: <20070809141310.GM27603@bitfolk.com>
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Hi Florian,

On Thu, Aug 09, 2007 at 09:15:53AM +0200, Rustedt, Florian wrote:
> On RAID 1, it is possible, to read two blocks in parallel to speed up, to=
o.
>=20
> I tried to measure this some weeks ago, but i couldn't get over the
> read-performance of a single disk on my raid 1, so that means, that the
> software-raid does not use this easy possibility to speed up?

Were you doing this with a single thread or multiple threads?  My
understanding is that for RAID-1, a single thread's IO will come
=66rom whichever component is knwon to be closest to where it needs to
start reading from.

If that's not correct I'd love to hear the reality!

Cheers,
Andy

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