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From: Chris Friesen <cfriesen@nortelnetworks.com>
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To: Linus Torvalds <torvalds@transmeta.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, Benjamin LaHaise <bcrl@redhat.com>,
       Pavel Machek <pavel@elf.ucw.cz>, Andrea Arcangeli <andrea@suse.de>,
       linux-kernel@vger.kernel.org, linux-aio@kvack.org
Subject: Re: [rfc] aio-core for 2.5.29 (Re: async-io API registration for2.5.29)
References: <Pine.LNX.4.44.0208010924050.14765-100000@home.transmeta.com>
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Linus Torvalds wrote:

> The only thing that I think makes it less than wonderful is really the
> fact that we cannot give an accurate measure for it. We can _say_ that
> what we count in microseconds, but it might turn out that instead of the
> perfect 1000000 ticks a second ther would really be 983671 ticks.

Would there be any benefit to using processor timestamps (rdtsc and friends) for
this if they are available?  I don't know the complexities of the interaction
with power management, that might make it infeasable.

Chris

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