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Date: Sun, 22 May 2005 03:59:15 +0100
From: Bruce M Simpson <bms@spc.org>
To: Stephan Uphoff <ups@tree.com>
Message-ID: <20050522025914.GD1108@empiric.icir.org>
References: <428FC00B.3080909@freebsd.org> <1116729865.1917.92.camel@palm>
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Cc: Colin Percival <cperciva@freebsd.org>,
	"freebsd-arch@freebsd.org" <freebsd-arch@freebsd.org>
Subject: Re: Scheduler fixes for hyperthreading
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On Sat, May 21, 2005 at 10:44:25PM -0400, Stephan Uphoff wrote:
> Beside benchmarking - is there any other real use for RDTSC ?
> Is there any use of RDTSC that system requiring the security cannot live
> without? (We could even try to emulate the instruction if we really need
> to)

A number of ports use RDTSC for high-resolution timing. The most obvious
examples being machine emulators mostly used for gaming (UAE and MAME
spring to mind, possibly also dosbox and others).

I daresay VMware probably uses RDTSC too.

BMS