From owner-freebsd-arch  Sun Jan 13 12:57:34 2002
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Date: Sun, 13 Jan 2002 12:56:53 -0800
From: Terry Lambert <tlambert2@mindspring.com>
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To: Peter Jeremy <peter.jeremy@alcatel.com.au>
Cc: Bruce Evans <bde@zeta.org.au>, Peter Wemm <peter@wemm.org>,
	Alfred Perlstein <bright@mu.org>, Kelly Yancey <kbyanc@posi.net>,
	Nate Williams <nate@yogotech.com>,
	Daniel Eischen <eischen@pcnet1.pcnet.com>,
	Dan Eischen <eischen@vigrid.com>, Archie Cobbs <archie@dellroad.org>,
	arch@FreeBSD.ORG
Subject: Re: Request for review: getcontext, setcontext, etc
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	 <20020112205919.E5372-100000@gamplex.bde.org> <20020114074238.S561@gsmx07.alcatel.com.au>
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Peter Jeremy wrote:
> Also, how expensive is a DNA trap?  Would it be cheaper overall to
> always load FPU context on a switch - this is more expensive for
> processes that don't use FP, but saves a DNA trap per context switch
> (assuming they use FP in that slice) for those that do.

I'd like to see a kernel that saves FPU state always benched
against a kernel that does lazy binding, using the "make world
weighted average of three runs" benchmark.

-- Terry

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