From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: Flows! Offload them. Date: Sat, 28 Feb 2015 15:02:33 -0500 (EST) Message-ID: <20150228.150233.90829668077433241.davem@davemloft.net> References: <20150226161705.GH1973@nanopsycho.lan> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: jiri@resnulli.us, simon.horman@netronome.com, netdev@vger.kernel.org, nhorman@tuxdriver.com, andy@greyhouse.net, tgraf@suug.ch, dborkman@redhat.com, ogerlitz@mellanox.com, jesse@nicira.com, jpettit@nicira.com, joestringer@nicira.com, john.r.fastabend@intel.com, jhs@mojatatu.com, sfeldma@gmail.com, f.fainelli@gmail.com, roopa@cumulusnetworks.com, linville@tuxdriver.com, shrijeet@gmail.com, gospo@cumulusnetworks.com, bcrl@kvack.org To: therbert@google.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:34147 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752856AbbB1UCh (ORCPT ); Sat, 28 Feb 2015 15:02:37 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: Tom Herbert Date: Thu, 26 Feb 2015 10:15:24 -0800 > But, routing (aka switching) in the stack is not configured through > TC. We have a whole forwarding and routing infrastructure (eg. > iproute) with optimizations that allow routes to be cached in > sockets, etc. To me, it seems like offloading that basic functionality > is a prerequisite before attempting to offload more advanced policy > mechanisms of TC, netfilter, etc. +1 I think this is the most important post in this entire thread. The current proposal here is jumping the gun by several weeks if not months. We have no idea what roadblocks or design barriers we will hit with just plain L2 and L3 forwarding yet. Therefore it is premature to move over to making major decisions about flow offloading before we've made more progress with the more fundamental (and in my opinion much more important) offload facilities. Jiri, if you want to implement an example set of classifiers in software that can completely replace openvswitch's datapath, that's fine. And it's a completely independant task to designing how we'll offload flows to hardware in the future.