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From: Christoph Rohland <cr@sap.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: tigran@veritas.com (Tigran Aivazian), mikpe@csd.uu.se (Mikael Pettersson),
        ledzep37@home.com (Jordan),
        linux-kernel@vger.kernel.org (Linux Kernel)
Subject: Re: Error in x86 CPU capabilities starting with test5/6
In-Reply-To: <E13wkLK-0000bP-00@the-village.bc.nu>
Organisation: SAP LinuxLab
Date: 17 Nov 2000 13:51:11 +0100
In-Reply-To: Alan Cox's message of "Fri, 17 Nov 2000 12:10:07 +0000 (GMT)"
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Hi Alan,

On Fri, 17 Nov 2000, Alan Cox wrote:
> Even checking the cpuinfo for the TSC should be done with care, and
> its far far better to use gettimeofday unless doing very tiny
> timings (eg for optimising code paths)

gettimeofday is _way_ to slow for a lot of every day uses. So
applications will use rdtsc until we have some really fast
(non-syscall) way to have high resolution time diffs.

Greetings
		Christoph

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