From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [ofa-general] Re: [PATCH RFC] RDMA/CMA: Allocate PS_TCP portsfrom the host TCP port space. Date: Sun, 19 Aug 2007 00:23:37 -0700 (PDT) Message-ID: <20070819.002337.06589160.davem@davemloft.net> References: <20070817.234405.66176298.davem@davemloft.net> <000001c7e22e$b7b90f00$29c8180a@amr.corp.intel.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: rdreier@cisco.com, jeff@garzik.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, general@lists.openfabrics.org To: sean.hefty@intel.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:55083 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750709AbXHSHXi (ORCPT ); Sun, 19 Aug 2007 03:23:38 -0400 In-Reply-To: <000001c7e22e$b7b90f00$29c8180a@amr.corp.intel.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: "Sean Hefty" Date: Sun, 19 Aug 2007 00:01:07 -0700 > Millions of Infiniband ports are in operation today. Over 25% of the top 500 > supercomputers use Infiniband. The formation of the OpenFabrics Alliance was > pushed and has been continuously funded by an RDMA customer - the US National > Labs. RDMA technologies are backed by Cisco, IBM, Intel, QLogic, Sun, Voltaire, > Mellanox, NetApp, AMD, Dell, HP, Oracle, Unisys, Emulex, Hitachi, NEC, Fujitsu, > LSI, SGI, Sandia, and at least two dozen other companies. IDC expects > Infiniband adapter revenue to triple between 2006 and 2011, and switch revenue > to increase six-fold (combined revenues of 1 billion). Scale these numbers with reality and usage. These vendors pour in huge amounts of money into a relatively small number of extremely large cluster installations. Besides the folks doing nuke and whole-earth simulations at some government lab, nobody cares. And part of the investment is not being done wholly for smart economic reasons, but also largely publicity purposes. So present your great Infiniband numbers with that being admitted up front, ok? It's relevance to Linux as a general purpose operating system that should be "good enough" for %99 of the world is close to NIL. People have been pouring tons of money and research into doing stupid things to make clusters go fast, and in such a way that make zero sense for general purpose operating systems, for ages. RDMA is just one such example. BTW, I find it ironic that you mention memory bandwidth as a retort, as Roland's favorite stateless offload devil, TSO, deals explicity with lowering the per-packet BUS bandwidth usage of TCP. LRO offloading does likewise.