From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
To: bloat@lists.bufferbloat.net
Subject: Re: [Bloat] Hardware upticks
Date: Tue, 5 Jan 2016 20:29:30 +0100 [thread overview]
Message-ID: <20160105192930.GA7803@sesse.net> (raw)
In-Reply-To: <568C1209.5050403@taht.net>
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 */
--
Homepage: https://www.sesse.net/
next prev parent reply other threads:[~2016-01-05 19:29 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-05 6:37 Jonathan Morton
2016-01-05 17:42 ` Aaron Wood
2016-01-05 18:27 ` Jonathan Morton
2016-01-05 18:57 ` Dave Täht
2016-01-05 19:29 ` Steinar H. Gunderson [this message]
2016-01-05 19:37 ` Dave Täht
2016-01-05 20:13 ` David Collier-Brown
2016-01-05 20:27 ` Stephen Hemminger
2016-01-05 21:10 ` Jonathan Morton
2016-01-05 23:20 ` Steinar H. Gunderson
2016-01-05 23:17 ` Steinar H. Gunderson
2016-01-05 21:36 ` Benjamin Cronce
2016-01-06 0:01 ` Steinar H. Gunderson
2016-01-06 0:06 ` Stephen Hemminger
2016-01-06 0:22 ` Steinar H. Gunderson
2016-01-06 0:53 ` Stephen Hemminger
2016-01-06 0:55 ` Steinar H. Gunderson
2016-01-06 1:22 ` Stephen Hemminger
2016-01-06 6:18 ` Jonathan Morton
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