From: Phillip Susi <psusi@ubuntu.com>
To: George Spelvin <linux@horizon.com>, keld@keldix.com, rspadim@gmail.com
Cc: linux-raid@vger.kernel.org, matthew.garman@gmail.com
Subject: Re: Why are reads not balanced across my RAID-1?
Date: Thu, 30 Jan 2014 15:05:10 -0500 [thread overview]
Message-ID: <52EAB076.8070301@ubuntu.com> (raw)
In-Reply-To: <20140125011832.23432.qmail@science.horizon.com>
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On 1/24/2014 8:18 PM, George Spelvin wrote:
> Obviously, if I added disks and striped across them, sequential
> performance would go up. This is an actual RAID-10 layout. But
> it's not useful unless I buy more disks.
No, md can do raid10 on two disks, just not in the near layout. The
offset layout with a sufficiently large chunk size mostly does what
you want. I recently set myself up with a 3 disk array like that and
it pushes 500 MB/s using cheap, run of the mill 1 TB WD Blue drives.
The offset layout gives slightly better performance than far ( as long
as you use a sufficiently large chunk size ), and can be resized,
unlike far.
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next prev parent reply other threads:[~2014-01-30 20:05 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-24 10:47 Why are reads not balanced across my RAID-1? George Spelvin
2014-01-24 12:04 ` keld
2014-01-24 13:33 ` George Spelvin
2014-01-25 1:48 ` keld
2014-01-24 14:56 ` Matt Garman
2014-01-24 16:50 ` Mathias Burén
2014-01-24 17:49 ` keld
2014-01-24 18:22 ` Roberto Spadim
2014-01-25 1:18 ` George Spelvin
2014-01-30 20:05 ` Phillip Susi [this message]
2014-01-25 17:52 ` Robert L Mathews
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