From owner-freebsd-hackers@FreeBSD.ORG  Mon Apr 27 13:46:30 2009
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id CD811106566B
	for <freebsd-hackers@freebsd.org>; Mon, 27 Apr 2009 13:46:30 +0000 (UTC)
	(envelope-from joerg@britannica.bec.de)
Received: from www.sonnenberger.org (www.ostsee-abc.de [62.206.222.50])
	by mx1.freebsd.org (Postfix) with ESMTP id 883888FC1A
	for <freebsd-hackers@freebsd.org>; Mon, 27 Apr 2009 13:46:30 +0000 (UTC)
	(envelope-from joerg@britannica.bec.de)
Received: from britannica.bec.de (www.sonnenberger.org [192.168.1.10])
	by www.sonnenberger.org (Postfix) with ESMTP id 4202F6670C
	for <freebsd-hackers@freebsd.org>;
	Mon, 27 Apr 2009 15:46:23 +0200 (CEST)
Received: by britannica.bec.de (Postfix, from userid 1000)
	id 6F41B1BDC9E; Mon, 27 Apr 2009 15:46:18 +0200 (CEST)
Date: Mon, 27 Apr 2009 15:46:18 +0200
From: Joerg Sonnenberger <joerg@britannica.bec.de>
To: freebsd-hackers@freebsd.org
Message-ID: <20090427134617.GA688@britannica.bec.de>
Mail-Followup-To: freebsd-hackers@freebsd.org
References: <200904270150.31912.pieter@degoeje.nl>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <200904270150.31912.pieter@degoeje.nl>
User-Agent: Mutt/1.5.19 (2009-01-05)
Subject: Re: ACPI-fast default timecounter, but HPET 83% faster
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 27 Apr 2009 13:46:31 -0000

On Mon, Apr 27, 2009 at 01:50:31AM +0200, Pieter de Goeje wrote:
> While fiddling with the sysctl kern.timecounter.hardware, I found out
> that on my system HPET is significantly faster than ACPI-fast.

I did some extensive testing on a variety of AMD and Intel boards and
never found a system where HPET is slower than ACPI-fast.

In addition, HPET provides a higher resolution.

Joerg