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From: Wolfgang Denk <wd@denx.de>
To: Dave Chinner <david@fromorbit.com>
Cc: Emmanuel Florac <eflorac@intellique.com>,
	linux-raid@vger.kernel.org,
	Justin Piszcz <jpiszcz@lucidpixels.com>,
	xfs@oss.sgi.com
Subject: Re: Optimize RAID0 for max IOPS?
Date: Tue, 25 Jan 2011 13:45:09 +0100	[thread overview]
Message-ID: <20110125124509.D76D6BB0B9@gemini.denx.de> (raw)
In-Reply-To: <20110125083643.GE28803@dastard>

Dear Dave Chinner,

In message <20110125083643.GE28803@dastard> you wrote:
>
> Oh, despite $subject being "RAID0" the filesystems being tested are
> on RAID5 and RAID6 with very small chunk sizes on slow SATA drives.
> This is smelling like a case of barrier IOs on software raid on
> cheap storage....

Right. [Any way to avoid these, btw?]  I got side-tracked by the
comments about the new (to me) delaylog mount option to xfs; as the
results were not exactly as exp[ected I though it might be interesting
to report these.

But as the subject says, my current topic is tuning RAID0 to avoid
exactly this type of bottleneck; or rather looking for tunable options
on RAID0

Best regards,

Wolfgang Denk

--
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
PLEASE NOTE: Some Quantum Physics Theories Suggest That When the Con-
sumer Is Not Directly Observing This Product, It May Cease  to  Exist
or Will Exist Only in a Vague and Undetermined State.

  reply	other threads:[~2011-01-25 12:45 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-18 21:01 Optimize RAID0 for max IOPS? Wolfgang Denk
2011-01-18 22:18 ` Roberto Spadim
2011-01-19  7:04   ` Wolfgang Denk
2011-01-18 23:15 ` Stefan /*St0fF*/ Hübner
2011-01-19  0:05   ` Roberto Spadim
2011-01-19  7:11     ` Wolfgang Denk
2011-01-19  8:18       ` Stefan /*St0fF*/ Hübner
2011-01-19  8:29         ` Jaap Crezee
2011-01-19  9:32           ` Jan Kasprzak
2011-01-19  7:10   ` Wolfgang Denk
2011-01-19 19:21   ` Wolfgang Denk
2011-01-19 19:50     ` Roberto Spadim
2011-01-19 22:36       ` Stefan /*St0fF*/ Hübner
2011-01-19 23:09         ` Roberto Spadim
2011-01-19 23:18           ` Roberto Spadim
2011-01-20  2:48             ` Keld Jørn Simonsen
2011-01-20  3:53               ` Roberto Spadim
2011-01-21 19:34             ` Wolfgang Denk
2011-01-21 20:03               ` Roberto Spadim
2011-01-21 20:04                 ` Roberto Spadim
2011-01-24 14:40     ` CoolCold
2011-01-24 15:25       ` Justin Piszcz
2011-01-24 20:48         ` Wolfgang Denk
2011-01-24 21:57         ` Wolfgang Denk
2011-01-24 23:03           ` Dave Chinner
2011-01-25  7:39             ` Emmanuel Florac
2011-01-25  8:36               ` Dave Chinner
2011-01-25 12:45                 ` Wolfgang Denk [this message]
2011-01-25 12:51                   ` Emmanuel Florac
2011-01-24 20:43       ` Wolfgang Denk
2011-01-25 17:10 ` Christoph Hellwig
2011-01-25 18:41   ` Wolfgang Denk
2011-01-25 21:35     ` Christoph Hellwig
2011-01-26  7:16       ` Wolfgang Denk
2011-01-26  8:32         ` Stan Hoeppner
2011-01-26  8:42           ` Wolfgang Denk
2011-01-26  9:38         ` Christoph Hellwig
2011-01-26  9:41           ` CoolCold

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