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From: Andy Smith <andy@lug.org.uk>
To: linux-raid <linux-raid@vger.kernel.org>
Subject: paralellism of device use in md
Date: Tue, 17 Jan 2006 12:09:27 +0000	[thread overview]
Message-ID: <20060117120927.GU7017@strugglers.net> (raw)

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I'm wondering: how well does md currently make use of the fact there
are multiple devices in the different (non-parity) RAID levels for
optimising reading and writing?

For example, are *writes* to a 2 device RAID-0 approaching twice as
fast as to a single device?  If not, are they any faster at all?
Are reads from a 2 device RAID-1 twice as fast as from a single
device?  If there are benefits, how quickly do they degrade to
nothing as disks are added?

What does the picture look like for reads and writes to a 4 device
RAID-10?

Sorry if my subject line isn't clear, but I coudn't think of a
better way to put it.

Thanks,
Andy

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             reply	other threads:[~2006-01-17 12:09 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-01-17 12:09 Andy Smith [this message]
2006-01-17 23:04 ` paralellism of device use in md Neil Brown
2006-01-18  0:23 ` Tim Moore
2006-01-18  7:41   ` Mario 'BitKoenig' Holbe
2006-01-18  8:16     ` Mario 'BitKoenig' Holbe
2006-01-18 17:55       ` Francois Barre
2006-01-18 23:34         ` Neil Brown
2006-01-22 16:43           ` Tuomas Leikola
2006-01-19 11:30         ` Mario 'BitKoenig' Holbe
2006-01-18  9:50 ` Andy Smith

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