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Date: Sat, 12 Nov 2005 18:37:11 +1100
From: Peter Jeremy <PeterJeremy@optushome.com.au>
To: Pyun YongHyeon <pyunyh@gmail.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: poor fdc(4) performance
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On Sat, 2005-Nov-12 16:18:15 +0900, Pyun YongHyeon wrote:
>I encountered a P3 SMP system that shows poor fdc(4) performance.
>But when I use larger block size, say 36b, it seems it works
>as expected.

36b is one track.  My suspicion is that the system isn't fast enough
to read sequential blocks, one at a time, so you're forced to wait
a complete revolution (plus a bit) for each block you read.

-- 
Peter Jeremy