RAID-3? (was: cvs commit: src MAINTAINERS)
Greg 'groggy' Lehey
grog at FreeBSD.org
Sat Aug 21 01:46:19 PDT 2004
On Saturday, 21 August 2004 at 10:37:57 +0200, Pawel Jakub Dawidek wrote:
> On Sat, Aug 21, 2004 at 06:02:07PM +0930, Greg 'groggy' Lehey wrote:
> +> On Saturday, 21 August 2004 at 10:06:14 +0200, Pawel Jakub Dawidek wrote:
> +> > So as you can see there are no difference in reading (actually
> +> > reading in degraded mode is even a bit faster, hard to say why).
> +> I would have half expected this. If you're reading parity as well,
> +> then without spindle sync it will take longer for three I/Os to
> +> complete than 2.
> I'm not sure if I understand you well...
I think you understood what I said, but it looks like it was based on
> In RAID3, when array is complete you don't use parity component for
> reading at all. So in complete mode, as well as in degraded mode
> RAID3 is using only two components for reading.
OK, that seems reasonable. phk suggested that you would check parity
Yes, in that case you'd expect things to be identical.
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