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From: Ming Zhang <mingz@ele.uri.edu>
To: John Madden <jmadden@ivytech.edu>
Cc: Tyler <pml@dtbb.net>, Linux RAID <linux-raid@vger.kernel.org>
Subject: Re: raid0 low performance
Date: Fri, 01 Jul 2005 08:41:03 -0400	[thread overview]
Message-ID: <1120221664.5507.25.camel@localhost.localdomain> (raw)
In-Reply-To: <50513.168.91.5.7.1120186660.squirrel@localhost>

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On Thu, 2005-06-30 at 21:57 -0500, John Madden wrote:
> > useage during the tests?  even PCI 32bit, 33mhz should be able to hit
> > 133 Mbytes per second I believe.  What are you writing *from* ? dev/zero
> 
> ~127MB/s is the theoretical bus speed of PCI/33.  Actual throughput is much less
> than that, of course.
> 
> But you're not on a 33MHz bus, you should be at at least 66MHz (and info in /proc
which one? i can not find. :P could u tell me? thx


> should tell you).  Given the lack of performance increase though, I'm guessing
> you're either pegging the bus or the CPU, not yet the throughput of the kernel
> itself.  Does the program block in disk wait when running?
yes, it write synchronously. so it is wait.


but my friend run same code on a 3ware 4 disk raid0 and get 140MB
easily.

similar box, P4 2.8G 1G ram. supermicro board.


> 
> John
> 
> (Go Rams)
> 
> 
> 

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  reply	other threads:[~2005-07-01 12:41 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-07-01  2:15 raid0 low performance Ming Zhang
2005-07-01  2:28 ` Tyler
2005-07-01  2:57   ` John Madden
2005-07-01 12:41     ` Ming Zhang [this message]
2005-07-01 12:54       ` John Madden
2005-07-01 13:10         ` Ming Zhang
2005-07-01 12:32   ` Ming Zhang
2005-07-01 12:55 ` Guy
2005-07-01 13:17   ` Ming Zhang
2005-07-01 13:54     ` Ming Zhang
2005-07-05  0:13       ` Mark Hahn
2005-07-05  0:26         ` Ming Zhang
2005-07-05 13:19           ` Ming Zhang
2005-07-01 14:42     ` Ming Zhang

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