From owner-freebsd-hackers@FreeBSD.ORG  Wed Nov  2 07:31:42 2005
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Date: Wed, 2 Nov 2005 01:31:39 -0600 (CST)
From: Mike Silbersack <silby@silby.com>
To: Viktor Vasilev <viktor.vasilev@stud.tu-darmstadt.de>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: select(2) timeout precision
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On Tue, 1 Nov 2005, Viktor Vasilev wrote:

> With FreeBSD 5.4-RELEASE I almost constantly get ~20000 microseconds
> delta. That is with 100HZ kernel on PIII 500MHz or Sempron 64 2800+

Put kern.hz=1000 in /boot/loader.conf to kick it up to 1000Hz, that should 
improve the accuracy a lot.

The optimizations in the url someone else posted should probably be 
integrated into FreeBSD, but moving to a higher Hz setting is a necessity 
in either case.

Mike "Silby" Silbersack