From owner-freebsd-net Tue Oct 26 17:35:28 1999 Delivered-To: freebsd-net@freebsd.org Received: from mail-relay2.yahoo.com (mail-relay2.yahoo.com [206.251.17.77]) by hub.freebsd.org (Postfix) with ESMTP id A960514C92 for ; Tue, 26 Oct 1999 17:35:25 -0700 (PDT) (envelope-from jayanth@yahoo-inc.com) Received: from borogove.yahoo.com (borogove.yahoo.com [205.216.162.65]) by mail-relay2.yahoo.com (8.9.3/8.9.3) with ESMTP id RAA06352; Tue, 26 Oct 1999 17:35:25 -0700 (PDT) Received: from yahoo-inc.com (milk.yahoo.com [206.132.89.117]) by borogove.yahoo.com (8.9.3/8.9.3) with ESMTP id RAA21848; Tue, 26 Oct 1999 17:35:25 -0700 (PDT) Message-ID: <381648CC.B57E06BF@yahoo-inc.com> Date: Tue, 26 Oct 1999 17:35:24 -0700 From: jayanth X-Mailer: Mozilla 4.08 [en] (X11; I; FreeBSD 2.2.8-STABLE i386) MIME-Version: 1.0 To: Alex Rousskov Cc: freebsd-net@FreeBSD.ORG Subject: Re: TCP throughput vs number of aliases References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Alex Rousskov wrote: > Hi there, > > We use FreeBSD 3.1 to benchmark Web caching proxies. We want to > use a [very] large number of IP addresses for simulated clients and > servers in the benchmark setup. However, we are limited by the number of > machines we can dedicate to the tests. Naturally, we are using interface > aliases to create IP addresses. > > With the number of aliases above 600+ we are monitoring a sudden > and significant drop in TCP throughput (measured using simple netperf > tests). The graph and some details of the setup are at > > http://www.ircache.net/~wessels/Junk/aliases/ > > We would like to use more than 600 aliases; probably 2,000-5,000 aliases > per box without the loss of performance. > > Can anybody recommend a solution? > > Thank you, > > Alex. > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-net" in the body of the message The code in ip_input.c seems to step through the list of all ip addresses for that interface. It is probably stepping thro' all the alias addresses I wonder if that is the problem. jayanth To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message