From owner-freebsd-net@FreeBSD.ORG Wed Sep 13 17:22:55 2006 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 3709116A403; Wed, 13 Sep 2006 17:22:55 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0083343D6D; Wed, 13 Sep 2006 17:22:53 +0000 (GMT) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [209.31.154.41]) by cyrus.watson.org (Postfix) with ESMTP id E95A546BFF; Wed, 13 Sep 2006 13:22:46 -0400 (EDT) Date: Wed, 13 Sep 2006 18:22:46 +0100 (BST) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Marcelo Gardini do Amaral In-Reply-To: <20060911195521.GD63300@registro.br> Message-ID: <20060913182019.R50147@fledge.watson.org> References: <2a41acea0608301145j7bbed961j33ce903a27d8963d@mail.gmail.com> <20060904130827.GE12975@registro.br> <20060911195521.GD63300@registro.br> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-net@freebsd.org, freebsd-stable@freebsd.org Subject: Re: DNS query performance 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: Wed, 13 Sep 2006 17:22:55 -0000 On Mon, 11 Sep 2006, Marcelo Gardini do Amaral wrote: > I would like to discuss a little bit more about UDP performance. I've made > some tests and the results may have some value here. > > In this test is easy to see that there is something different in the FreeBSD > 6 branch. > > I made a benchmark with bind 9.3.2 (without threads support) and nsd 3.0.1 > (1 server forked) on a HP Proliant Dual AMD Opteron 2.4GHz among FreeBSD > 4.11, 6.1 and Linux kernel 2.6.15, all of them for i386 systems. I used this > simple zone file: Are you able to boot a 7.x kernel on this box? An as yet un-MFC'd optimization to the UDP send path is present in the 7.x kernel, suggested by ISC, which significantly improves threaded BIND9 performance. I've not benchmarked unthreaded BIND9 with the change. If you want to test specifically the before/after case for that change, you can find the reference to sosend_dgram in src/sys/netinet/udp_usrreq.c and swap it to sosend, which restores the old behavior. Robert N M Watson Computer Laboratory University of Cambridge