From owner-freebsd-hackers@FreeBSD.ORG  Wed Jul 11 14:44:45 2012
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From: Paul Albrecht <albrecht@glccom.com>
To: Alexander Motin <mav@FreeBSD.org>
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Date: Wed, 11 Jul 2012 09:44:44 -0500
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Cc: "davide@FreeBSD.org" <davide@FreeBSD.org>,
	"freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>,
	Harti Brandt <hartmut.brandt@dlr.de>
Subject: Re: [[SPAM]] Re: kqueue timer timeout period
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On Wed, 2012-07-11 at 04:42 -0500, Alexander Motin wrote:
> Hi.
> 
> Historically FreeBSD used completely different hardware time sources for 
> time keeping and time events. Not sure about 5%, but the last could be 
> less precise in some cases. FreeBSD 9.0, depending on hardware, can be 
> more precise because of using same time source in both cases. Also there 
> is ongoing GSoC project now by Davide Italiano to handle sub-HZ 
> resolution for time events. Present tests show reaching 20 microseconds 
> precision; and I think it can be improved further.
> 

I'm definitely not getting getting 20 millisecond timing with freebsd
kqueue which surprised me because I get it with linux
linuxfd_create/read using the same hardware.

-- 
Paul Albrecht