From owner-freebsd-current  Wed Apr  1 18:01:03 1998
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To: current@FreeBSD.ORG
Subject: Re: current-digest V4 #79 
In-reply-to: Your message of "Wed, 01 Apr 1998 15:36:40 PST."
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Date: Wed, 01 Apr 1998 18:01:01 -0800
From: "Gregory P. Smith" <greg@nas.nasa.gov>
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> Date: Wed, 1 Apr 1998 15:58:15 +0200 (CEST)
> From: Andrzej Bialecki <abial@nask.pl>
> Subject: MMX & ip checksums
> 
> Hi!
> 
> I've heard rumours that someone from Linux camp implemented ip checksums
> using MMX extensions, which caused significant performance boost in
> network operations... Can anyone confirm/deny this? If it's true, it would
> be worthwhile to take a look at it...
> 
> Andrzej Bialecki

I think that would violate the Kernel's "never use floating point" rule
because MMX uses the FP registers.  (and on Intel's MMX implementation
supposedly has a "large" context switch time between MMX and floating
point mode).

[Assuming MMX instructions would even be useful for the cause]

Greg


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