From owner-freebsd-questions@FreeBSD.ORG  Sat Sep 29 16:45:18 2007
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 2E4B316A417
	for <freebsd-questions@freebsd.org>;
	Sat, 29 Sep 2007 16:45:18 +0000 (UTC)
	(envelope-from kris@FreeBSD.org)
Received: from weak.local (hub.freebsd.org [IPv6:2001:4f8:fff6::36])
	by mx1.freebsd.org (Postfix) with ESMTP id 83FCF13C455
	for <freebsd-questions@freebsd.org>;
	Sat, 29 Sep 2007 16:45:17 +0000 (UTC)
	(envelope-from kris@FreeBSD.org)
Message-ID: <46FE8120.4040608@FreeBSD.org>
Date: Sat, 29 Sep 2007 18:45:20 +0200
From: Kris Kennaway <kris@FreeBSD.org>
User-Agent: Thunderbird 2.0.0.6 (Macintosh/20070728)
MIME-Version: 1.0
To: freebsd-questions@freebsd.org
References: <80f4f2b20709240723m121aad88ofaf728f384dd6c20@mail.gmail.com>	<20070924184415.7bffd7d2@gumby.homeunix.com.>	<46FE790A.1000101@FreeBSD.org>
	<20070929163116.GA1748@olymp.home>
In-Reply-To: <20070929163116.GA1748@olymp.home>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: Questions on the scheduler
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 29 Sep 2007 16:45:18 -0000

Oliver Herold wrote:
> Are there any numbers or technical papers? Just out of curiosity.

I ran a mysql benchmark against Dragonfly-current and FreeBSD 7 on an 
8-core machine (one of the workloads that FreeBSD now performs very well 
at) and found 0 scaling on dragonfly.  Their developers confirmed that 
the kernel is still entirely giant locked (as in FreeBSD 4) so no SMP 
performance benefits are possible.

The email thread is here:

   http://leaf.dragonflybsd.org/mailarchive/users/2007-05/msg00134.html

although the linked graph is offline.  The FreeBSD curve was essentially 
this one (FreeBSD has improved further since then):

   http://people.freebsd.org/~kris/scaling/scaling.png

with dragonfly a flat line at ~500 tps independent of load.

Kris