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Date: Mon, 31 Oct 2005 18:18:35 +0800
From: David Xu <davidxu@freebsd.org>
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To: Robert Watson <rwatson@freebsd.org>
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Cc: Alexander Leidinger <Alexander@Leidinger.net>, freebsd-current@freebsd.org
Subject: Re: TSC instead of ACPI: powerd doesn't
	work	anymore	(to	be	expected?)
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Robert Watson wrote:
> 
> 
> It has been suggested that the former can operate quite well with 
> significantly reduced quality.  It has alos been suggested that most 
> applications could operate fine with somewhat reduced quality, but that 
> the API definitions don't say anything about how to specify application 
> quality requirements vs performance requirements for time measurement.

Can we change gettimeofday and clock_gettime to lower resolution now?
I think 1000hz/s is enough for most applications, since a thread can
never sleep shorter than a tick for years. We can introduce
hrtime_t clock_gethrtime(clockid_t clock) to get hi-resolution time
as the one seen in RTLinux, or gethrtime() as seen in Solaris (Daniel
Eischen said?)

David Xu