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Date: Tue, 8 Jan 2013 12:16:03 +0100
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Alexander Motin <mav@FreeBSD.org>
Subject: Re: [RFC/RFT] calloutng
Message-ID: <20130108111603.GA30469@onelab2.iet.unipi.it>
References: <50CCAB99.4040308@FreeBSD.org> <50CE5B54.3050905@FreeBSD.org>
 <50D03173.9080904@FreeBSD.org> <20121225232126.GA47692@alchemy.franken.de>
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Cc: Davide Italiano <davide@FreeBSD.org>, freebsd-arch@FreeBSD.org,
 FreeBSD Current <freebsd-current@FreeBSD.org>,
 Marius Strobl <marius@alchemy.franken.de>
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On Tue, Jan 08, 2013 at 12:55:27PM +0200, Alexander Motin wrote:
> On 06.01.2013 18:20, Luigi Rizzo wrote:
...
> > I think that for the time being it would be useful to run at least
> > one set of tests with kern.timecounter.alloweddeviation=0 so we can
> > tell how close we get to the required timeouts
> 
> May be just to be sure, because it should not significantly affect
> results of the 1us tests, as 5% of 1us is much less then numbers we see
> there.

to clarify - i don't mind if we are 50-100us (absolute error) off the
requested timeout for short intervals, but i want to be sure
that this error can be achieved also for large requests.

cheers
luigi