Re: SW-RAID0 Performance problems

From: David Rees (dbr@greenhydrant.com)
Date: Sat Apr 14 2001 - 02:04:33 EST


On Fri, Apr 13, 2001 at 06:28:20PM +0200, Andreas Peter wrote:
> Am Freitag, 13. April 2001 18:07 schrieb David Rees:
>
> > Cconfig and setup looks OK.
> >
> > What happens if your run hdparm -t /dev/hda and /dev/hdc at the same time?
>
> Good idea!
> The performance is only ~11MB/sec per disk
> There is a bottleneck somewhere...

OK, so it's not the RAID setup. There's two things that can cause this.
One is that DMA is turned off (what does hdparm /dev/hda and hdparm
/dev/hdc show?), the second was that the drives are on the same channel
(which obviously isn't the case here). Can you verify that the drives are
in DMA mode?

-Dave
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This archive was generated by hypermail 2b29 : Sun Apr 15 2001 - 21:00:22 EST