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Date: Wed, 25 May 2005 10:53:42 -0600 (MDT)
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To: bms@spc.org
From: "M. Warner Losh" <imp@bsdimp.com>
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References: <428FC00B.3080909@freebsd.org> <1116729865.1917.92.camel@palm>
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Cc: freebsd-arch@freebsd.org, cperciva@freebsd.org, ups@tree.com
Subject: Re: Scheduler fixes for hyperthreading
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In message: <20050522025914.GD1108@empiric.icir.org>
            Bruce M Simpson <bms@spc.org> writes:
: 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).

Which also makes it hard to emulate, since that adds a lot of
overhead to the numbers...

Warner