From owner-freebsd-net@FreeBSD.ORG Thu May 31 14:33:46 2007 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 5327A16A481 for ; Thu, 31 May 2007 14:33:46 +0000 (UTC) (envelope-from freebsd@laws.ms) Received: from mail2.worria.com (mail2.worria.com [205.234.133.139]) by mx1.freebsd.org (Postfix) with SMTP id 0CEB513C447 for ; Thu, 31 May 2007 14:33:45 +0000 (UTC) (envelope-from freebsd@laws.ms) Received: (qmail 2223 invoked by uid 399); 31 May 2007 14:07:05 -0000 Received: from unknown (HELO ?203.218.158.34?) (sales@worria.com@203.218.158.34) by mail2.worria.com with SMTP; 31 May 2007 14:07:05 -0000 X-Originating-IP: 203.218.158.34 Message-ID: <465ED66F.30902@laws.ms> Date: Thu, 31 May 2007 22:06:39 +0800 From: Pang User-Agent: Thunderbird 1.5.0.12 (Windows/20070509) MIME-Version: 1.0 To: freebsd-questions@freebsd.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-net@freebsd.org Subject: Download speed and TCPIP window sizing X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 31 May 2007 14:33:46 -0000 Hello, Recently, I have leased a rack in Asianetcom and some bandwidth. However, the speed for my curcuit is substantially slower than my provider's company site. The provider said my circuit and their one are treated exactly the same way. Below is the URL for the download: My circuit*: http://203.192.137.194/test.rar ANC curcuit: http://www.asianetcom.com/pub/communications/AsiaNetcomNews_2006Q2.pdf *This server is using FreeBSD 6.2 patch 4 with Apache in the port tree. The kernel is custom built but I haven't made any modification in sysctl I have asked many techs in Asianetcom and they blamed on TCPIP window sizing. I am not sure what it is, so I do a search in Google and find the following: http://www.vad1.com/tcp-throughput-limit.html After reading the article above, I feel the situation is very similar. But, from my understanding, the download speed should be proportional to the ping speed. However, test done on Canada is much higher (about 3 times higher) than in US while the ping is very similar. Could anyone tell me whether my understanding on Window sizing correct? Also, is there any way to alter the window sizing in freebsd or apache? Thanks Pang