From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [evb] RE: [PATCH][RFC] net/bridge: add basic VEPA support Date: Mon, 10 Aug 2009 17:28:15 +0200 Message-ID: <200908101728.15649.arnd@arndb.de> References: <4A7EB0AC.2030104@Voltaire.com> <20090810082037.17b352c2@nehalam> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Or Gerlitz , "Paul Congdon (UC Davis)" , anna.fischer@hp.com, netdev@vger.kernel.org, bridge@lists.linux-foundation.org, davem@davemloft.net, adobriyan@gmail.com, virtualization@lists.linux-foundation.org, "evb@yahoogroups.com" To: Stephen Hemminger Return-path: Received: from moutng.kundenserver.de ([212.227.17.10]:58136 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753043AbZHJP2T (ORCPT ); Mon, 10 Aug 2009 11:28:19 -0400 In-Reply-To: <20090810082037.17b352c2@nehalam> Sender: netdev-owner@vger.kernel.org List-ID: On Monday 10 August 2009, Stephen Hemminger wrote: > On Sun, 09 Aug 2009 14:19:08 +0300, Or Gerlitz wrote: > > Looking in macvlan_set_multicast_list() it acts in a similar manner to > > macvlan_set_mac_address() in the sense that it calls dev_mc_sync(). I > > assume what's left is to add macvlan_hash_xxx multicast logic to > > map/unmap multicast groups to what macvlan devices want to receive them > > and this way the flooding can be removed, correct? > > The device can just flood all multicast packets, since the filtering > is done on the receive path anyway. But we'd still have to copy the frames to user space (for both macvtap and raw packet sockets) and exit from the guest to inject it into its stack, right? I guess for multicast heavy workloads, we could save a lot of cycles by throwing the frames away as early as possible. How common are those setups in virtual servers though? Arnd <><