From: Andy Smith <andy@strugglers.net>
To: linux-raid@vger.kernel.org
Subject: Re: Can extremely high load cause disks to be kicked?
Date: Fri, 1 Jun 2012 19:25:24 +0000 [thread overview]
Message-ID: <20120601192524.GH3867@bitfolk.com> (raw)
In-Reply-To: <4FC81B85.8090807@hardwarefreak.com>
Hi Stan,
On Thu, May 31, 2012 at 08:31:49PM -0500, Stan Hoeppner wrote:
> On 5/31/2012 3:31 AM, Andy Smith wrote:
> > Now, is this sort of behaviour expected when under incredible load?
> > Or is it indicative of a bug somewhere in kernel, mpt driver, or
> > even flaky SAS controller/disks?
>
> It is expected that people know what RAID is and how it is supposed to
> be used. RAID is to be used for protecting data in the event of a disk
> failure and secondarily to increase performance. That is not how you
> seem to be using RAID.
Just to clarify, this was the hypervisor host. The VMs on it don't
use RAID themselves as that would indeed be silly.
> There are a number of scenarios where md RAID is better than hardware
> RAID and vice versa. Yours is a case where hardware RAID is superior,
> as no matter the host CPU load, drives won't get kicked offline as a
> result, as they're under the control of a dedicated IO processor (same
> for SAN RAID).
Fair enough, thanks.
Cheers,
Andy
next prev parent reply other threads:[~2012-06-01 19:25 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-31 8:31 Can extremely high load cause disks to be kicked? Andy Smith
2012-06-01 1:31 ` Stan Hoeppner
2012-06-01 3:15 ` Igor M Podlesny
2012-06-01 14:12 ` Stan Hoeppner
2012-06-01 15:19 ` Igor M Podlesny
2012-06-02 4:45 ` Stan Hoeppner
2012-06-02 7:57 ` Igor M Podlesny
2012-06-02 9:16 ` Stan Hoeppner
2012-06-01 19:25 ` Andy Smith [this message]
2012-06-02 5:47 ` Stan Hoeppner
2012-06-03 3:30 ` Andy Smith
2012-06-03 4:05 ` Igor M Podlesny
2012-06-03 22:05 ` Andy Smith
2012-06-04 1:55 ` Stan Hoeppner
2012-06-04 9:06 ` Igor M Podlesny
2012-06-03 6:49 ` Stan Hoeppner
2012-06-04 0:02 ` Andy Smith
2012-06-04 6:58 ` Stan Hoeppner
2012-06-04 4:13 ` NeilBrown
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