Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262512AbUKQT3m (ORCPT ); Wed, 17 Nov 2004 14:29:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262509AbUKQT2B (ORCPT ); Wed, 17 Nov 2004 14:28:01 -0500 Received: from advect.atmos.washington.edu ([128.95.89.50]:26813 "EHLO advect.atmos.washington.edu") by vger.kernel.org with ESMTP id S262408AbUKQT0H (ORCPT ); Wed, 17 Nov 2004 14:26:07 -0500 Message-ID: <419BA5C4.4020503@atmos.washington.edu> Date: Wed, 17 Nov 2004 11:25:56 -0800 From: Harry Edmon User-Agent: Mozilla Thunderbird 0.8 (X11/20040926) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Con Kolivas CC: Stephen Hemminger , linux-kernel@vger.kernel.org Subject: Re: Network slowdown from 2.6.7 to 2.6.9 References: <419A9151.2000508@atmos.washington.edu> <20041116163257.0e63031d@zqx3.pdx.osdl.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -12.775 () AWL,BAYES_00 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1562 Lines: 42 Tried your suggestion - no improvement. Con Kolivas wrote: > Stephen Hemminger writes: > >> On Tue, 16 Nov 2004 15:46:25 -0800 >> Harry Edmon wrote: >> >>> I have a system that is running a program that receives and sends >>> atmospheric data via TCP. Most of the data is either in little >>> packets (between 64 and 127 bytes) and large packets (between 1024 >>> and 1517). I am running this on a dual Xeon box (Tyan S2721-533 >>> motherboard) with 2 GB of memory and a Intel gigabit ethernet >>> (82546EB). I have been running this under 2.6.7. When I switch to >>> 2.6.9 on the same hardware, my network throughtput is cut by more >>> than half. All I can tell from looking at "netstat -s" is that my >>> TCP resets are orders of magnitude higher under 2.6.9 than 2.6.7. >>> Enclosed is my 2.6.7 and 2.6.9 config files. Anyone have any ideas >>> where I should look to find the problem? >> >> >> Do an OpenBSD or other firewall in the way that doesn't understand >> window >> scaling? OpenBSD pf doesn't correctly TCP window scaling so it ruins the >> throughput (typically 1/4 of expected). > > > Easiest way to see if this is responsible is to disable it and see if > the throughput improves > > echo 0 > /proc/sys/net/ipv4/tcp_window_scaling > > Cheers, > Con - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/