From owner-freebsd-questions@FreeBSD.ORG Mon Feb 18 12:44:45 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C53FD16A417 for ; Mon, 18 Feb 2008 12:44:45 +0000 (UTC) (envelope-from norgaard@locolomo.org) Received: from bifrost.locolomo.org (97.pool85-48-194.static.orange.es [85.48.194.97]) by mx1.freebsd.org (Postfix) with ESMTP id 7A39013C442 for ; Mon, 18 Feb 2008 12:44:45 +0000 (UTC) (envelope-from norgaard@locolomo.org) Received: from Home.local (32.Red-80-37-158.staticIP.rima-tde.net [80.37.158.32]) by bifrost.locolomo.org (Postfix) with ESMTP id 4F9183982D; Mon, 18 Feb 2008 13:44:44 +0100 (CET) Message-ID: <47B97DBB.7090406@locolomo.org> Date: Mon, 18 Feb 2008 13:44:43 +0100 From: Erik Norgaard User-Agent: Thunderbird 2.0.0.9 (Macintosh/20071031) MIME-Version: 1.0 To: Boldra References: <47B94EAE.3050002@boldra.com> <47B9567F.2080803@locolomo.org> <47B979A6.9040901@boldra.com> In-Reply-To: <47B979A6.9040901@boldra.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-questions@freebsd.org Subject: Re: network not performing - where to start? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 18 Feb 2008 12:44:45 -0000 Boldra wrote: > Can you point me to a man page or something for your suggestion "use > packet filtering statistics" ? Where do I start? If you have a firewall enabled this usually creates statistics on the packets sent and received. If not, you can create a simple filter that just passes everything. With packet filter something like pass on ed1 all should do, where ed1 is the name of you interface. It can show you just how much data is actually sent when you transfer that 100Mbyte file. I'm a bit outdated on the current situation, it's been a long time since I've had anything but FreeBSD to worry about - that is, I don't care about optimal performance for those who choose to use windows :) You will always loose something due to overhead in protocols on different levels, for example tcp send back ACK packets, using scp your system will also do encryption and decryption, etc. I recall once also experiencing performance issues when transfering data between linux and freebsd - that was more than 5 years ago, but I would always assume performance to be best between to equivalent systems. I don't know your brand of interface, but while the interface may formally support 100Mbit/s, in reality other things also affect performance, particularly cheap NICs perform bad in peak load, although they do communicate at 100Mbit. Don't ask me about details, but buffering is one of the issues AFAIK. Also, check MTU on the windows machines, that can be a killer if it forces fragmentation. I recall once that some set the MTU to 1492 or some other value. It can have significant impact on performance if MTUs differ and packets are fragmented. There is the MTU ping test: DOS> ping ip.n.u.m -f -l 1492 see http://help.expedient.com/broadband/mtu_ping_test.shtml Cheers, Erik