From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751241AbWDKWdd (ORCPT ); Tue, 11 Apr 2006 18:33:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751199AbWDKWdd (ORCPT ); Tue, 11 Apr 2006 18:33:33 -0400 Received: from smtp.osdl.org ([65.172.181.4]:26597 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751176AbWDKWdc (ORCPT ); Tue, 11 Apr 2006 18:33:32 -0400 Date: Tue, 11 Apr 2006 15:33:15 -0700 From: Stephen Hemminger To: Daniel Drake Cc: John Heffner , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: 2.6.17 regression: Very slow net transfer from some hosts Message-ID: <20060411153315.4132b477@localhost.localdomain> In-Reply-To: <443C2BBA.5010804@gentoo.org> References: <443C03E6.7080202@gentoo.org> <443C024C.2070107@psc.edu> <443C0B74.50305@gentoo.org> <443C09A7.2040900@psc.edu> <443C1738.20605@gentoo.org> <443C178B.3030805@psc.edu> <443C2BBA.5010804@gentoo.org> Organization: OSDL X-Mailer: Sylpheed-Claws 2.0.0 (GTK+ 2.8.6; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 11 Apr 2006 23:20:42 +0100 Daniel Drake wrote: > John Heffner wrote: > > This is almost certainly due to a buggy firewall that doesn't understand > > TCP window scaling. I've usually seen this in the past with OpenBSD > > firewalls. Do you have one of these in your path? > > At home I'm behind a Linux gateway box currently running 2.6.15-rc6 - I > am connected through ethernet to that. > > At my student house I am connected wirelessly to a Linksys WRT54Gv5 > router (the model that doesnt run Linux). > > I have reproduced it at both those locations (same ISP). > > This is very familiar, and I just found the article I was thinking of: > http://lwn.net/Articles/92727/ > > I was also hit by that bug, on the same collection of websites, but that > particular problem was fixed for 2.6.8 or so. So I guess it is extremely > likely that my ISP has broken routers. nmap isn't able to identify the > OS of any ISP routers in my path. We never fixed it, its kind of hard to fix other peoples equipment ;-) > > It's a huge ISP over here, so contacting them over technical matters is > not easy... > > Thanks, > Daniel > Turn off TCP window scaling, your performance will be limited but about as good as you can get with a corrupting firewall in between.