From owner-freebsd-stable@FreeBSD.ORG Tue Jul 12 06:21:15 2005 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 596BB16A41C; Tue, 12 Jul 2005 06:21:15 +0000 (GMT) (envelope-from danny@cs.huji.ac.il) Received: from cs1.cs.huji.ac.il (cs1.cs.huji.ac.il [132.65.16.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id EBB7C43D46; Tue, 12 Jul 2005 06:21:14 +0000 (GMT) (envelope-from danny@cs.huji.ac.il) Received: from pampa.cs.huji.ac.il ([132.65.80.32]) by cs1.cs.huji.ac.il with esmtp id 1DsE8n-0004CT-NQ; Tue, 12 Jul 2005 09:21:13 +0300 X-Mailer: exmh version 2.7.0 06/18/2004 with nmh-1.0.4 To: freebsd-stable@freebsd.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 12 Jul 2005 09:21:13 +0300 From: Danny Braniss Message-ID: Cc: freebsd-net@freebsd.org Subject: tcp troughput weirdness X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Jul 2005 06:21:15 -0000 while checking out the quality of a switch, I came about a very disturbing dicovery: FreeBSD <-> Linux througput is MUCH better than FreeBSD <-> FreeBSD Setup: 2 blades in the same bladeserver, A running FreeBSD 5.4, B running Linux C is running FreeBSD 5.4 all are connected at 1gb. A -+ (FreeBSD) | B -+ (Linux) | [switch] | +---- [router] --- C (FreeBSD) A & B are on the same Vlan. iperf results: Interval Transfer Bandwidth A <=> B 0.0-10.0 sec 1.09 GBytes 939 Mbits/sec A <=> C 0.0-10.0 sec 515 MBytes 432 Mbits/sec B <=> C 0.0-10.0 sec 1.07 GBytes 918 Mbits/sec I've run the tests several times, and the numbers are very similar, so BIG Question: is there anything that can be tunned on the FreeBSD to better the throughput? danny