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Date: Tue, 5 Jan 2016 20:29:30 +0100
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
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Subject: Re: [Bloat] Hardware upticks
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On Tue, Jan 05, 2016 at 10:57:13AM -0800, Dave Täht wrote:
> Context switch time is probably one of the biggest hidden nightmares in
> modern OOO cpu architectures - they only go fast in a straight line. I'd
> love to see a 1ghz processor that could context switch in 5 cycles.

It's called hyperthreading? ;-)

Anyway, the biggest cost of a context switch isn't necessarily the time used
to set up registers and such. It's increased L1 pressure; your CPU is now
running different code and looking at (largely) different data.

/* Steinar */
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