From owner-freebsd-current@FreeBSD.ORG  Thu Jun  7 09:30:29 2007
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
X-Original-To: freebsd-current@freebsd.org
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id 9F84116A46E
	for <freebsd-current@freebsd.org>; Thu,  7 Jun 2007 09:30:29 +0000 (UTC)
	(envelope-from thompsa@FreeBSD.org)
Received: from heff.fud.org.nz (203-109-251-39.static.bliink.ihug.co.nz
	[203.109.251.39])
	by mx1.freebsd.org (Postfix) with ESMTP id 48EA613C48A
	for <freebsd-current@freebsd.org>; Thu,  7 Jun 2007 09:30:29 +0000 (UTC)
	(envelope-from thompsa@FreeBSD.org)
Received: by heff.fud.org.nz (Postfix, from userid 1001)
	id C99D01CC5D; Thu,  7 Jun 2007 21:30:27 +1200 (NZST)
Date: Thu, 7 Jun 2007 21:30:27 +1200
From: Andrew Thompson <thompsa@FreeBSD.org>
To: Abdullah Ibn Hamad Al-Marri <almarrie@gmail.com>
Message-ID: <20070607093027.GA4784@heff.fud.org.nz>
References: <499c70c0706070210v39f7016hbd80e9780902e992@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <499c70c0706070210v39f7016hbd80e9780902e992@mail.gmail.com>
User-Agent: Mutt/1.5.13 (2006-08-11)
Cc: freebsd-current@freebsd.org
Subject: Re: Why not remove polling(4) from 7.0?
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 07 Jun 2007 09:30:29 -0000

On Thu, Jun 07, 2007 at 12:10:31PM +0300, Abdullah Ibn Hamad Al-Marri wrote:
> Hello Guys,
> 
> Almost all cases polling(4) adds additional latency.
> There are some cases that polling(4) helps a little but most cases it 
> wouldn't.
> 
> So why not remove it or switch to adaptive polling as em(4) instead of
> resorting to polling?

Are you just talking about em(4) or removing polling for all drivers? It
is helpful in some cases, for example I run FreeBSD on a Nortel
contivity 1010 box where interrupts do not work on the fxp interface and
yet its quite usable with polling mode.

Its not enabled by default so its up to the user if they want to make
use of it.


cheers,
Andrew