Message-ID: <4AF9DA6B.803@zytor.com>
Date: Tue, 10 Nov 2009 13:26:03 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Matt Thrailkill <matt.thrailkill@gmail.com>
CC: Pavel Machek <pavel@ucw.cz>, Willy Tarreau <w@1wt.eu>,
       Avi Kivity <avi@redhat.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Matteo Croce <technoboy85@gmail.com>,
       Sven-Haegar Koch <haegar@sdinet.de>, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org
Subject: Re: i686 quirk for AMD Geode
References: <20091110052711.GA15338@1wt.eu> <4AF9435F.2070103@redhat.com> 	<20091110105642.215804e0@lxorguk.ukuu.org.uk> <4AF99E04.8080704@zytor.com> 	<20091110172454.3c4481f2@lxorguk.ukuu.org.uk> <4AF9B5AB.5010800@zytor.com> 	<4AF9C3EF.6000705@redhat.com> <4AF9C6AB.8080006@zytor.com> 	<20091110201602.GA26633@1wt.eu> <20091110205445.GB1407@ucw.cz> <a91053ef0911101321he1cf15cx8d15d747b371fde4@mail.gmail.com>
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On 11/10/2009 01:21 PM, Matt Thrailkill wrote:
> On Tue, Nov 10, 2009 at 12:54 PM, Pavel Machek <pavel@ucw.cz> wrote:
>> *One* CMOV in the inner loop will make your performance go down 20x.
> 
> This is 20x slower than not running at all, right?

And that's the fundamental win of doing a fullscale emulator: you will
always be able to run, at *some* performance level.

	-hpa

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