From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932084AbWFSPP2 (ORCPT ); Mon, 19 Jun 2006 11:15:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932175AbWFSPP2 (ORCPT ); Mon, 19 Jun 2006 11:15:28 -0400 Received: from mail13.syd.optusnet.com.au ([211.29.132.194]:52201 "EHLO mail13.syd.optusnet.com.au") by vger.kernel.org with ESMTP id S932084AbWFSPP1 (ORCPT ); Mon, 19 Jun 2006 11:15:27 -0400 From: Con Kolivas To: linux-kernel@vger.kernel.org Subject: Re: 2.6.17: slow (as hell) tcp inbound transfers Date: Tue, 20 Jun 2006 01:15:02 +1000 User-Agent: KMail/1.9.3 Cc: Brice Figureau , Vincent Vanackere References: <1150725598.4985.27.camel@localhost.localdomain> <65258a580606190717t2cc5b28eg10fb4d64fe5ec1f3@mail.gmail.com> <1150729187.4985.41.camel@localhost.localdomain> In-Reply-To: <1150729187.4985.41.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200606200115.02492.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 20 June 2006 00:59, Brice Figureau wrote: > Hi, > > On Mon, 2006-06-19 at 16:17 +0200, Vincent Vanackere wrote: > > On 6/19/06, Brice Figureau wrote: > > > Now to the problem: I just finished the installation of a brand new > > > 2.6.17 on a Dell PowerEdge 2850 which was running 2.6.16.19 really > > > fine, and I'm encountering a strange issue. > > > > > > It seems that TCP inbound transfers (using either curl, or scp) are > > > really slow except when issued on our gigabit LAN. > > > > Could you try the following to see if it cures your problem ? > > > > echo 0 > /proc/sys/net/ipv4/tcp_window_scaling > > Yes, that fixed it: > # curl http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.17.tar.gz > > > /dev/null > > % Total % Received % Xferd Average Speed Time Time Time > Current > Dload Upload Total Spent Left > Speed > 0 49.3M 0 9856 0 0 2991 0 4:48:05 0:00:03 4:48:02 > 3680 > > # echo 0 > /proc/sys/net/ipv4/tcp_window_scaling > > # curl http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.17.tar.gz > > > /dev/null > > % Total % Received % Xferd Average Speed Time Time Time > Current > Dload Upload Total Spent Left > Speed > 1 49.3M 1 904k 0 0 86544 0 0:09:57 0:00:10 0:09:47 > 71173 > > Did something has changed between 2.6.16 and 2.6.17 regarding TCP window > scaling ? > > I remember a discussion on lklm aroung 2.6.7 or so that finally ended as > a bug in a firewall that wasn't handling TCP window scaling gracefully. > That's certainly my case, I'll will have a look to that. See: http://kerneltrap.org/node/6723 -- -ck