From owner-freebsd-net@FreeBSD.ORG  Sat Oct 30 11:32:23 2010
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 2AC511065673
	for <freebsd-net@freebsd.org>; Sat, 30 Oct 2010 11:32:23 +0000 (UTC)
	(envelope-from prt@prt.org)
Received: from smtp5.uk.umis.net (smtp5.uk.umis.net [217.65.166.40])
	by mx1.freebsd.org (Postfix) with ESMTP id E413A8FC12
	for <freebsd-net@freebsd.org>; Sat, 30 Oct 2010 11:32:22 +0000 (UTC)
Received: from www1.prt.org ([217.65.161.4] helo=2.32.24.172.in-addr.arpa)
	by smtp5.uk.umis.net with esmtpsa (TLSv1:AES256-SHA:256)
	(Exim 4.63 (FreeBSD)) (envelope-from <prt@prt.org>)
	id 1PC9fX-0009Iq-TG
	for freebsd-net@freebsd.org; Sat, 30 Oct 2010 11:32:20 +0000
Message-ID: <4CCC0243.8060507@prt.org>
Date: Sat, 30 Oct 2010 12:32:19 +0100
From: Paul Thornton <prt@prt.org>
User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US;
	rv:1.9.2.12) Gecko/20101027 Thunderbird/3.1.6
MIME-Version: 1.0
To: freebsd-net@freebsd.org
References: <1519248747.20101028232111@yandex.ru>	<1452146D-A590-4676-A662-14D0EEE82152@mac.com>	<606859717.20101029093926@yandex.ru>
	<FA2E3C9B-A1A1-4FB3-80AD-26F5518C1ABF@mac.com>
In-Reply-To: <FA2E3C9B-A1A1-4FB3-80AD-26F5518C1ABF@mac.com>
Content-Type: text/plain; charset=KOI8-R
Content-Transfer-Encoding: 8bit
X-Mailman-Approved-At: Sat, 30 Oct 2010 11:47:56 +0000
Subject: Re: Polling slows down bandwidth
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 30 Oct 2010 11:32:23 -0000

Hi,

On 29/10/2010 18:23, Chuck Swiger wrote:
> On Oct 28, 2010, at 11:39 PM, Коньков Евгений wrote:
>> so using polling on gigabit NICs is a bottle neck? and is cause of low performance, is not?
> 
> Simple answer is yes.  It should be possible that you could tune polling to get similar performance, or at least better performance than you see now, but the additional hardware capabilities of gigabit NICs are likely to outperform polling mode, just as polling mode can generally outperform old 100MBs ethernet NICs.

I have been using polling for a long time with em and fxp interfaces on
6.2 and 4.9 boxes that are working as routers.

I've been doing testing with FreeBSD 8 and em interfaces recently, and
my experience agrees with Chuck's statement - that polling makes things
worse when you use new (anything in the last 2 or 3 years) hardware with
good quality gigabit ethernet interfaces.

I've only really worked with bge and em but they have good high
performance without polling in 8.0 and 8.1

Paul.