linux-raid.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Stefan /*St0fF*/ Hübner" <stefan.huebner@stud.tu-ilmenau.de>
To: Wolfgang Denk <wd@denx.de>
Cc: Roberto Spadim <roberto@spadim.com.br>, linux-raid@vger.kernel.org
Subject: Re: Optimize RAID0 for max IOPS?
Date: Wed, 19 Jan 2011 09:18:53 +0100	[thread overview]
Message-ID: <4D369E6D.8020604@stud.tu-ilmenau.de> (raw)
In-Reply-To: <20110119071138.7B2D02FC@gemini.denx.de>

Am 19.01.2011 08:11, schrieb Wolfgang Denk:
> Dear Roberto Spadim,
> 
> In message <AANLkTi=v6yA_0OOfi2ymA67X0x+KsvV9VC5OgG+0DvKq@mail.gmail.com> you wrote:
>> maybe removing hwraid and using swraid may reduce speed (depend how
>> much cpu you use with hw and with sw)
>> what we can optimize? less I/O per seconds making as much useful
>> read/write data on array, how? good read/write algorithms for raid.
>> (for each device type, ssd, hd) but... like stefan, disks are your
>> bottleneck
> 
> No, they are not.  Run some benchmarks yourself if you don't believe
> me.

Lol - I wouldn't have answered in the first place if I didn't have any
expertise.  So suit yourself - as you don't bring up any real numbers
(remember: you've got the weird setup, you asked, you don't have enough
money for the enterprise solution - so ...) nobody who worked with 3ware
controllers will believe you.

> 
> Even a single disk drive is performing better than the hw RAID under
> this workload.

Well - that is the problem - simulate YOUR workload.  Actually I fear at
least one of your disks has a grown defect, which slows down / blocks
i/o.  Haven't seen any 9650SE RAID being slower than the same config in
a software raid.

> 
> Best regards,
> 
> Wolfgang Denk
> 


  reply	other threads:[~2011-01-19  8:18 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 [this message]
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
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

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4D369E6D.8020604@stud.tu-ilmenau.de \
    --to=stefan.huebner@stud.tu-ilmenau.de \
    --cc=linux-raid@vger.kernel.org \
    --cc=roberto@spadim.com.br \
    --cc=wd@denx.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).