From owner-freebsd-hackers@FreeBSD.ORG Thu Sep 19 20:03:39 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 8347D89E; Thu, 19 Sep 2013 20:03:39 +0000 (UTC) (envelope-from luigi@onelab2.iet.unipi.it) Received: from onelab2.iet.unipi.it (onelab2.iet.unipi.it [131.114.59.238]) by mx1.freebsd.org (Postfix) with ESMTP id 3712B265C; Thu, 19 Sep 2013 20:03:39 +0000 (UTC) Received: by onelab2.iet.unipi.it (Postfix, from userid 275) id 99B4E7300A; Thu, 19 Sep 2013 22:08:59 +0200 (CEST) Date: Thu, 19 Sep 2013 22:08:59 +0200 From: Luigi Rizzo To: George Neville-Neil Subject: Re: Network stack changes Message-ID: <20130919200859.GA68598@onelab2.iet.unipi.it> References: <521E41CB.30700@yandex-team.ru> <6BDA4619-783C-433E-9819-A7EAA0BD3299@neville-neil.com> <20130914142802.GC71010@onelab2.iet.unipi.it> <6ACABEE8-2C0F-435C-8766-7010A8E13042@neville-neil.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <6ACABEE8-2C0F-435C-8766-7010A8E13042@neville-neil.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-Mailman-Approved-At: Thu, 19 Sep 2013 20:58:40 +0000 Cc: "Alexander V. Chernikov" , Adrian Chadd , Andre Oppermann , "freebsd-hackers@freebsd.org" , "freebsd-arch@freebsd.org" , Luigi Rizzo , "Andrey V. Elsukov" , Gleb Smirnoff , FreeBSD Net , Olivier Cochard-Labb? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 19 Sep 2013 20:03:39 -0000 On Thu, Sep 19, 2013 at 03:54:34PM -0400, George Neville-Neil wrote: >=20 > On Sep 14, 2013, at 15:24 , Luigi Rizzo wrote: >=20 > >=20 > >=20 > > On Saturday, September 14, 2013, Olivier Cochard-Labb? wrote: > > > On Sat, Sep 14, 2013 at 4:28 PM, Luigi Rizzo wro= te: > > >> > > >> IXIA ? For the timescales we need to address we don't need an IXIA, > > >> a netmap sender is more than enough > > >> > > > > > > The great netmap generates only one IP flow (same src/dst IP and same > > > src/dst port). > >=20 > > True the sample app generates only one flow but it is trivial to modify= it to generate multiple flows. My point was, we have the ability to genera= te high rate traffic, as long as we do tolerate a .1-1us jitter. Beyond tha= t, you do need some ixia-like solution. > >=20 >=20 > On the bandwidth side, can a modern sender with netmap really do a full 1= 0G? I hate the cost of an > IXIA but I have not been able to destroy our stack as effectively with an= ything else. yes george, you can download the picobsd image http://info.iet.unipi.it/~luigi/netmap/20120618-netmap-picobsd-head-amd64.b= in and try for yourself. Granted this does not have all the knobs of an ixia but it can surely blast the full 14.88 Mpps to the link, and it only takes a bit of userspace programming to generate reasonably arbitrary streams of packets. A netmap sender/receiver is not CPU bound even with 1 core. cheers luigi =7F > Best, > George