Re: amr Serious performance issues

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Tue, Jan 11, 2011 at 05:13:20PM +0100, Hans Rosenfeld wrote:
> I don't remember whether I used any partitions at all. The machine is
> currently down and far away, so I can't check that right now. I think
> most of the time I tested with dd directly to the raw device, using
> block sizes 128k and 512k. Is a specially aligned partitioning supposed
> to make that much of a difference?

Yes. If the partition is not aligned on a stripe size, without write cache
you end up doing a read/modify/write cycle on each write, instead of a
write.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--