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From: "Keld Jørn Simonsen" <keld@dkuug.dk>
To: David Rees <drees76@gmail.com>
Cc: Jon Nelson <jnelson-suse@jamponi.net>,
	LinuxRaid <linux-raid@vger.kernel.org>
Subject: Re: help with bad performing raid6
Date: Fri, 31 Jul 2009 20:21:18 +0200	[thread overview]
Message-ID: <20090731182118.GB11756@rap.rap.dk> (raw)
In-Reply-To: <72dbd3150907301409t5ea20979gcf400e4c53a32d62@mail.gmail.com>

On Thu, Jul 30, 2009 at 02:09:19PM -0700, David Rees wrote:
> On Mon, Jul 27, 2009 at 12:19 PM, Jon Nelson<jnelson-suse@jamponi.net> wrote:
> > When I say "bad performance" I mean writes that vary down to 100KB/s
> > or less, as reported by rsync. The "average" end-to-end speed for
> > writing large (500MB to 5GB) files hovers around 3-4MB/s. This is over
> > 100 MBit.
> 
> That doesn't sound too unexpected.  rsync does a lot of reading and
> writing, so you're going to see less than network speeds.

rsync also does a lot of computing, so that is also a source of delay.
For faster cpu's the delay is not so big. I get near network speed ( 80
Mbit/s on a 100 Mbit/s LAN) between two of my faster machines.


best regards
keld

  reply	other threads:[~2009-07-31 18:21 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-27 19:19 help with bad performing raid6 Jon Nelson
2009-07-27 20:01 ` Robin Hill
2009-07-27 20:03   ` Jon Nelson
2009-07-27 20:44 ` John Robinson
2009-07-29 15:08 ` Bill Davidsen
2009-07-29 15:57   ` Jon Nelson
2009-07-29 16:06   ` Steven Haigh
2009-07-30 13:15     ` Bill Davidsen
2009-07-30 20:30       ` John Stoffel
2009-07-30 21:09 ` David Rees
2009-07-31 18:21   ` Keld Jørn Simonsen [this message]
2009-07-31 18:23     ` Jon Nelson
2009-07-31 19:19       ` David Rees
2009-07-31 19:31         ` Jon Nelson

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