From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: r8169 - disable flow-control? Date: Thu, 05 Mar 2009 21:08:48 +0000 Message-ID: <1236287329.3202.7.camel@achroite> References: <1236281743.10409.17.camel@alkisg> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org To: =?UTF-8?Q?=CE=86=CE=BB=CE=BA=CE=B7=CF=82_?= =?UTF-8?Q?=CE=93=CE=B5=CF=89=CF=81=CE=B3=CF=8C=CF=80=CE=BF=CF=85=CE=BB?= =?UTF-8?Q?=CE=BF=CF=82?= Return-path: Received: from smarthost02.mail.zen.net.uk ([212.23.3.141]:38090 "EHLO smarthost02.mail.zen.net.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751101AbZCEVIx (ORCPT ); Thu, 5 Mar 2009 16:08:53 -0500 In-Reply-To: <1236281743.10409.17.camel@alkisg> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 2009-03-05 at 21:35 +0200, =CE=86=CE=BB=CE=BA=CE=B7=CF=82 =CE=93= =CE=B5=CF=89=CF=81=CE=B3=CF=8C=CF=80=CE=BF=CF=85=CE=BB=CE=BF=CF=82 wrot= e: > Hello, >=20 > Is there any way to disable flow control for NICs using the r8169 > driver? >=20 > It would be really valuable in the following (sadly very common) > scenario: > * r8169 gigabit NIC on the server > * unmanaged gigabit switch that supports flow control negotiation > * 100Mbps clients >=20 > E.g. in LTSP labs, the server can send data at ~900Mbps with flow > control off, but with flow control on the bandwidth drops to ~90Mbps. > Detailed explanation of the problem: > http://virtualthreads.blogspot.com/2006/02/beware-ethernet-flow-contr= ol.html >=20 > If the current code doesn't support it, would it be possible to add a > module parameter for this? Generally you should be able to control this using ethtool, not a modul= e parameter. However r8169 does not implement this operation yet. Ben. --=20 Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.