From: Brendan Conoboy <blc@redhat.com>
To: david@lang.hm
Cc: Neil Brown <neilb@suse.de>, Wakko Warner <wakko@animx.eu.org>,
linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org
Subject: Re: limits on raid
Date: Mon, 18 Jun 2007 12:07:59 -0600 [thread overview]
Message-ID: <4676C9FF.7060607@redhat.com> (raw)
In-Reply-To: <Pine.LNX.4.64.0706181026170.12717@asgard.lang.hm>
david@lang.hm wrote:
> I plan to test the different configurations.
>
> however, if I was saturating the bus with the reconstruct how can I fire
> off a dd if=/dev/zero of=/mnt/test and get ~45M/sec whild only slowing
> the reconstruct to ~4M/sec?
>
> I'm putting 10x as much data through the bus at that point, it would
> seem to proove that it's not the bus that's saturated.
I am unconvinced. If you take ~1MB/s for each active drive, add in SCSI
overhead, 45M/sec seems reasonable. Have you look at a running iostat
while all this is going on? Try it out- add up the kb/s from each drive
and see how close you are to your maximum theoretical IO.
Also, how's your CPU utilization?
--
Brendan Conoboy / Red Hat, Inc. / blc@redhat.com
next prev parent reply other threads:[~2007-06-18 18:07 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-06-15 2:58 limits on raid david
2007-06-15 3:05 ` Neil Brown
2007-06-15 3:43 ` david
2007-06-15 3:58 ` Neil Brown
2007-06-15 9:13 ` David Chinner
2007-06-15 22:21 ` Neil Brown
2007-06-15 11:10 ` Avi Kivity
2007-06-15 16:23 ` Jan Engelhardt
2007-06-15 17:20 ` Avi Kivity
2007-06-15 21:59 ` Neil Brown
2007-06-16 17:23 ` Avi Kivity
2007-06-17 13:00 ` Andi Kleen
2007-06-18 4:57 ` David Chinner
2007-06-21 2:56 ` Neil Brown
2007-06-21 6:39 ` David Chinner
2007-06-21 6:45 ` david
2007-06-21 8:59 ` David Greaves
2007-06-21 17:00 ` Mark Lord
2007-06-21 11:00 ` David Chinner
2007-06-21 12:40 ` Mattias Wadenstein
2007-06-21 14:40 ` Justin Piszcz
2007-06-21 16:48 ` david
2007-06-21 18:30 ` Martin K. Petersen
2007-06-21 20:08 ` Nix
2007-06-16 2:03 ` Wakko Warner
2007-06-16 3:47 ` Neil Brown
2007-06-16 4:40 ` Dan Merillat
2007-06-16 7:48 ` david
2007-06-16 13:38 ` David Greaves
2007-06-16 17:16 ` david
2007-06-17 17:16 ` Bill Davidsen
2007-06-18 17:20 ` Brendan Conoboy
2007-06-18 17:28 ` david
2007-06-18 18:03 ` Lennart Sorensen
2007-06-18 18:12 ` david
2007-06-18 18:33 ` Lennart Sorensen
2007-06-18 18:40 ` david
2007-06-18 19:11 ` Brendan Conoboy
2007-06-18 20:52 ` david
2007-06-18 21:46 ` Wakko Warner
2007-06-18 21:56 ` david
2007-06-18 22:00 ` Brendan Conoboy
2007-06-19 20:11 ` Lennart Sorensen
2007-06-19 20:51 ` david
2007-06-19 15:07 ` Phillip Susi
2007-06-19 19:28 ` david
2007-06-18 18:07 ` Brendan Conoboy [this message]
2007-06-18 18:16 ` david
2007-06-16 13:33 ` David Greaves
2007-06-17 1:44 ` dean gaudet
2007-06-21 3:01 ` Neil Brown
2007-06-21 8:49 ` David Greaves
2007-06-16 14:08 ` Wakko Warner
2007-06-17 1:47 ` dean gaudet
2007-06-17 13:28 ` Wakko Warner
2007-06-17 17:28 ` dean gaudet
2007-06-17 19:30 ` Wakko Warner
2007-06-17 19:54 ` dean gaudet
2007-06-17 20:46 ` david
2007-06-17 20:44 ` david
2007-06-17 17:14 ` Bill Davidsen
2007-06-21 23:03 ` Bill Davidsen
2007-06-22 2:24 ` Neil Brown
2007-06-22 8:10 ` David Greaves
2007-06-22 9:51 ` david
2007-06-22 12:39 ` David Greaves
2007-06-22 16:00 ` Bill Davidsen
2007-06-22 16:55 ` David Greaves
2007-06-22 18:41 ` david
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