From mboxrd@z Thu Jan 1 00:00:00 1970 From: Franco Fichtner Subject: Re: [PATCH net-next-2.6] rps: consistent rxhash Date: Tue, 20 Apr 2010 16:03:17 +0200 Message-ID: <4BCDB425.9050007@lastsummer.de> References: <1271452358.16881.4486.camel@edumazet-laptop> <1271520633.16881.4754.camel@edumazet-laptop> <20100419.130905.210660275.davem@davemloft.net> <20100419.132318.192086187.davem@davemloft.net> <1271709121.3845.94.camel@edumazet-laptop> <1271743164.3845.128.camel@edumazet-laptop> <1271750198.3845.216.camel@edumazet-laptop> <4BCDA2B5.4060609@lastsummer.de> <1271769404.7895.10.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Changli Gao , David Miller , therbert@google.com, netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from host64.kissl.de ([213.239.241.64]:59929 "EHLO host64.kissl.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754751Ab0DTOD1 (ORCPT ); Tue, 20 Apr 2010 10:03:27 -0400 In-Reply-To: <1271769404.7895.10.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: Eric Dumazet wrote: > Le mardi 20 avril 2010 =C3=A0 14:48 +0200, Franco Fichtner a =C3=A9cr= it : >=20 >> I thought about this for some time... >> >> Do we really need the port numbers here at all? A simple >> addr1^addr2 can provide a good enough pointer for >> distribution amongst CPUs. >> >> The real connection tracking is better done locally at the >> corresponding CPU. That way a potential cache miss can be >> avoided and the still needed hash calculation for >> connection tracking will be offloaded. >> >=20 > Yes, doing the port test/swap is useful in the loopback case=20 > (addr1 =3D=3D addr2). >=20 > This is probably a bit convoluted, but David (and me) found this > funny ;) >=20 >=20 It is funny, but I fail to see the big picture of the firewall / conntrack application here. It looks like this is needed for local netperf tests to impress, but it's a quite special use case, isn't it?