raid3 is slow

[Pawel Jakub Dawidek]

On Wed, Mar 28, 2007 at 06:21:34AM -0700, R. B. Riddick wrote:
> > # atacontrol mode ad0
> > current mode = UDMA100
> > # atacontrol mode ad1
> > current mode = UDMA100
> > # atacontrol mode ad2
> > current mode = UDMA100
> > # atacontrol mode ad3
> > current mode = UDMA100
> > # atacontrol mode ad6
> > current mode = SATA150
> >
> Looks good...

Does it? It seems there are two disks per ata channel, which is very bad
for performance.

I suggesting trying this:

	# apply "dd if=/dev/ad%1 if=/dev/null bs=1m count=250 &" 0 1 2 3 6

and once it completes try this:

	# dd if=/dev/raid3/<name> of=/dev/null bs=1m count=1000

and send the results here.

-- 
Pawel Jakub Dawidek                       http://www.wheel.pl
pjd at FreeBSD.org                           http://www.FreeBSD.org
FreeBSD committer                         Am I Evil? Yes, I Am!
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