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To: John Baldwin <jhb@freebsd.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 30 Nov 2009 14:27:23 EST."
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Date: Mon, 30 Nov 2009 21:03:46 +0000
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Cc: Attilio Rao <attilio@freebsd.org>, arch@freebsd.org,
	Scott Long <scottl@samsco.org>
Subject: Re: sglist(9) 
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In message <200911301427.23166.jhb@freebsd.org>, John Baldwin writes:
>On Sunday 29 November 2009 6:27:49 pm Scott Long wrote:

>It actually does get used by the nvidia driver, but so far in what I have
>done in my jhb_bio branch I have tried several different approaches which
>is why the API is as verbose as it is.

I would warn equally against rigorous simplification and gratuitous
generalization in this, I've tried both approaches in prototypes and
neither works out well from an API point of view.

The insight that expended CPU cycles are practially unmeasurable
in this context should not be forgotten, even in the quest to
get ever higher transactions per second numbers.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.