From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamal Hadi Salim Subject: Re: [patch net-next v3 02/17] net: make vid as a parameter for ndo_fdb_add/ndo_fdb_del Date: Tue, 25 Nov 2014 11:57:40 -0500 Message-ID: <5474B504.1080208@mojatatu.com> References: <1416911328-10979-1-git-send-email-jiri@resnulli.us> <1416911328-10979-3-git-send-email-jiri@resnulli.us> <5474A25C.3080505@mojatatu.com> <5474AC18.8040809@cumulusnetworks.com> <5474AF53.8030709@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Jiri Pirko , netdev@vger.kernel.org, davem@davemloft.net, nhorman@tuxdriver.com, andy@greyhouse.net, tgraf@suug.ch, dborkman@redhat.com, ogerlitz@mellanox.com, jesse@nicira.com, pshelar@nicira.com, azhou@nicira.com, ben@decadent.org.uk, stephen@networkplumber.org, jeffrey.t.kirsher@intel.com, vyasevic@redhat.com, xiyou.wangcong@gmail.com, edumazet@google.com, sfeldma@gmail.com, f.fainelli@gmail.com, linville@tuxdriver.com, jasowang@redhat.com, ebiederm@xmission.com, nicolas.dichtel@6wind.com, ryazanov.s.a@gmail.com, buytenh@wantstofly.org, aviadr@mellanox.com, nbd@openwrt.org, alexei.starovoitov@gmail.com, Neil.Jerram@metaswitch.com, ronye@mellanox.com, simon.horman@netronome.com, alexander.h.duyck@redhat.com, john.ronciak@intel.com, mleitner@redhat.com, shrijeet@gmail.com, gospo@cumulusnetworks.com, bcrl@kvack.org To: John Fastabend , Roopa Prabhu Return-path: Received: from mail-ig0-f169.google.com ([209.85.213.169]:56162 "EHLO mail-ig0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751028AbaKYQ5o (ORCPT ); Tue, 25 Nov 2014 11:57:44 -0500 Received: by mail-ig0-f169.google.com with SMTP id hl2so7102615igb.4 for ; Tue, 25 Nov 2014 08:57:43 -0800 (PST) In-Reply-To: <5474AF53.8030709@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: On 11/25/14 11:33, John Fastabend wrote: > On 11/25/2014 08:19 AM, Roopa Prabhu wrote: > I agree its needed but your already out of sync for some period of time > why the software/hardware tables are being programmed. There is no global > sw/hw commit operation. > > I'm not sure it matters if the time being out of sync is a touch longer > because we go to user space to fix it. But agreed it can be supported. > Recent netfilter has 2 phase commit built in. Maybe we can generalize that? Note, there are use cases where it is important to do rollbacks. If i am doing a distributed router, then to make sure a FIB/NH entries are properly synced in across the cluster is extremely important. You cant justify letting a few packets sneak in the wrong path. in other words, strong consistency is important. Having said that things can be worked around (and i would not use 2pc for the example use case i gave); however, that doesnt negate the fact we need it. cheers, jamal