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To: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 22 Aug 2005 10:33:20 +0200."
	<20050822083320.GA32668@stud.fit.vutbr.cz> 
Date: Mon, 22 Aug 2005 10:38:41 +0200
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Cc: freebsd-current@freebsd.org, Giorgos Keramidas <keramida@freebsd.org>,
	Kris Kennaway <kris@obsecurity.org>
Subject: Re: [PATCH]: fdalloc optimization 
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In message <20050822083320.GA32668@stud.fit.vutbr.cz>, Divacky Roman writes:

>    N           Min           Max        Median           Avg        Stddev
>x 100         39957        959570         41444      87169.69     201011.84
>+ 100         37786        962107         38766      66353.09     158258.74
>No difference proven at 95.0% confidence
>
>anyway - commenting out duplicate code MUST speed it up, maybe insignificantly
>but still ;)

It used to be that life was that simple, but with three levels of caches and
deep pipelines it isn't anymore.

But taken from the other side: you can also read this as your patch does no
damage to performance, so if code clarity is improved (havn't looked at your
patch myself) then that would be another good reason.

-- 
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.