From owner-freebsd-hardware  Tue Feb 25 00:22:57 1997
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Date: Tue, 25 Feb 1997 19:19:41 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199702250819.TAA02011@godzilla.zeta.org.au>
To: ken@stox.pr.mcs.net, msmith@atrad.adelaide.edu.au
Subject: Re: Memory speed of P6-200 (256k)
Cc: freebsd-hardware@freebsd.org
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>As Bruce has observed, this makes for very healthy IDE performance,
>which is what this whole thread started with.

Er, no, fast copying reduces buffer cache overheads.  Buffer cache
overheads are almost large enough to significantly reduce the advantages
of busmastering DMA over (slow) PIO.

Bruce