From owner-freebsd-current@FreeBSD.ORG Mon Jul 13 23:13:20 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4AE401065672 for ; Mon, 13 Jul 2009 23:13:20 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: from mail-yw0-f172.google.com (mail-yw0-f172.google.com [209.85.211.172]) by mx1.freebsd.org (Postfix) with ESMTP id 0733D8FC0C for ; Mon, 13 Jul 2009 23:13:19 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: by ywh2 with SMTP id 2so549389ywh.3 for ; Mon, 13 Jul 2009 16:13:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=a0ygWftqL8d2QzyZwVGTCkOjsFImDMPftWluSRUyTOQ=; b=FrSBOcIHOcKBAM5ZSn00PSGDbEkDOxjCLPEh0awAQ+m+9PUmwo9MpGd+f4roImK1Yj YNOZneTItUBW2IGvlzBebFkOXzX1q3QwynB/xp5l8YnU+GbcpKX+Q9DpwAQK/03k5PlS hzBrlK7dfk9KXvi5EquX17Bfc7AZbas/WyYrc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=Mub0Y0M1m4uAczaWichoy9RJohFlj5x1WzoqK8LNWrcJwshrpSRZ2r6H596OVvWAu1 K8GXGLui88VB38upeHOc1o4w64MH8DvYYAKaar+XMeivxzkiaSJH8fmrLyrueiwrT2l3 tOQVUded+nE+al9mZrgIbVy7ikS8VRabQLEPE= MIME-Version: 1.0 Sender: mat.macy@gmail.com Received: by 10.100.250.16 with SMTP id x16mr7985485anh.25.1247526799498; Mon, 13 Jul 2009 16:13:19 -0700 (PDT) In-Reply-To: <563461.85958.qm@web63902.mail.re1.yahoo.com> References: <563461.85958.qm@web63902.mail.re1.yahoo.com> Date: Mon, 13 Jul 2009 16:13:19 -0700 X-Google-Sender-Auth: 3d3b7265748b60c3 Message-ID: <3c1674c90907131613v69890449nf973d763781f2ea7@mail.gmail.com> From: Kip Macy To: Barney Cordoba Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-current@freebsd.org Subject: Re: Flowtables -- any tuning hints? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 13 Jul 2009 23:13:20 -0000 The flowtable was initially developed so that ECMP could support stateful load-balancing. In some ways it is a stop-gap for other areas. > Its only a misconception if you think its the only way to do things, which > in itself is a misconception. I'm not at liberty to discuss specifics so i can't defend myself properly. > > I will say that designing a 10gb/s "system" that doesnt work well with a large number of flows kind of misses the target, don't you think? If the only target that you care about is IP forwarding, I can respond with an emphatic "yes". If you're running web servers, NFS servers, stateful L3 load balancers, and many other applications, i.e. the majority of FreeBSD users, I can likewise respond with an emphatic "no". There are in fact quite a lot of users of 10Gbps that don't have hundreds of thousands of simultaneous peers. > The people who need 10gb/s are isps, universities and telcos; all of whom have a large number of flows. So I'm not sure exactly who is going to benefit from the work. There seems to be something unusual about the "large number of prefixes" crowd in that any facility that doesn't directly benefit them is not worth having. You are not the first to step up and sneer with contempt, and yet do nothing to address the architectural flaws that hamper forwarding performance for your workload, and you will not be the last. Cheers, Kip