From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: Multiqueue and virtualization WAS(Re: [PATCH 3/3] NET: [SCHED] Qdisc changes and sch_rr added for multiqueue Date: Fri, 29 Jun 2007 17:58:24 +0200 Message-ID: <46852C20.8000501@trash.net> References: <46840AF5.4020209@trash.net> <20070628.212032.108743475.davem@davemloft.net> <1183117415.5156.61.camel@localhost> <4684F41B.9080309@trash.net> <1183121670.5188.16.camel@localhost> <46850450.6040608@trash.net> <46852632.5050707@candelatech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: hadi@cyberus.ca, David Miller , peter.p.waskiewicz.jr@intel.com, netdev@vger.kernel.org, jeff@garzik.org, auke-jan.h.kok@intel.com To: Ben Greear Return-path: Received: from stinky.trash.net ([213.144.137.162]:47574 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759876AbXF2P6k (ORCPT ); Fri, 29 Jun 2007 11:58:40 -0400 In-Reply-To: <46852632.5050707@candelatech.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Ben Greear wrote: > Patrick McHardy wrote: > >> Right, but the current bridging code always uses promiscous mode >> and its nice to avoid that if possible. Looking at the code, it >> should be easy to avoid though by disabling learning (and thus >> promisous mode) and adding unicast filters for all static fdb entries. >> > > I am curious about why people are so hot to do away with promisc mode. > It seems to me > that in a modern switched environment, there should only very rarely be > unicast packets received > on an interface that does not want to receive them. I don't know if that really was Dave's reason to handle it in a driver. > Could someone give a quick example of when I am wrong and promisc mode > would allow > a NIC to receive a significant number of packets not really destined for > it? In a switched environment it won't have a big effect, I agree. It might help avoid receiving unwanted multicast traffic, which could be more significant than unicast. Anyways, why be wasteful when it can be avoided .. :)