From owner-freebsd-net@FreeBSD.ORG Wed Sep 21 13:53:05 2005 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9930A16A41F for ; Wed, 21 Sep 2005 13:53:05 +0000 (GMT) (envelope-from m.jakeman@lancaster.ac.uk) Received: from errol.lancs.ac.uk (errol.lancs.ac.uk [148.88.0.66]) by mx1.FreeBSD.org (Postfix) with ESMTP id 48C3143D81 for ; Wed, 21 Sep 2005 13:52:54 +0000 (GMT) (envelope-from m.jakeman@lancaster.ac.uk) Received: from marl.lancs.ac.uk ([148.88.1.10]) by errol.lancs.ac.uk with esmtp (Exim 4.52) id 1EI51p-0000JG-JK for freebsd-net@freebsd.org; Wed, 21 Sep 2005 14:52:53 +0100 Received: from ina044000004.lancs.ac.uk ([194.80.37.87]) by marl.lancs.ac.uk with esmtp (Exim 4.52) id 1EI51p-0001n0-O8 for freebsd-net@freebsd.org; Wed, 21 Sep 2005 14:52:53 +0100 From: Matthew Jakeman Organization: Lancaster University To: freebsd-net@freebsd.org Date: Wed, 21 Sep 2005 14:58:19 +0000 User-Agent: KMail/1.8 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200509211458.19739.m.jakeman@lancaster.ac.uk> Subject: iperf results X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: m.jakeman@lancaster.ac.uk List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Sep 2005 13:53:05 -0000 Hi, Some colleagues and myself have performed some simple tests on various OS's using iperf to simply fire packets from one pc to another over ethernet to test a few characteristics such as packet loss, jitter etc between IPv4 and IPv6. The configuration for all three OS's were 'out of the box' installs. The results we got back from that are strange for FreeBSD with regards to the packet loss iperf reports and I was wondering if anyone has any ideas why they might be as they are. The image at the link below shows the packet loss results for windows, Linux and FreeBSD for comparison! As you can see the packet loss for v6 is substantially less than v4 on FreeBSD, however this is still substantially larger than for the other two OS's, does anyone have any idea why this might be? http://www.mjakeman.co.uk/images/4v6tests.jpg One other question is that I tried altering the Mbuf size in the kernel config to 1500 using "options MSIZE=1500" but when i try to recompile the kernel with this value i get a compilation error "/usr/src/sys/kern/kern_mbuf.c: error: size of array `__assert123' is negative", be aware I have not looked much into why this might be happening at present but if there is a hard upper limit or any other reason that this might be happening I would be grateful to be informed of it. Thanks in advance for any replies Matt