From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Subject: Re: [PATCH V3 2/2] bonding support for IPv6 transmit hashing Date: Sat, 30 Jun 2012 12:38:15 -0700 Message-ID: <4FEF55A7.6070502@8192.net> References: <4FEE99EE.2000001@8192.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Hannes Frederic Sowa Return-path: Received: from smtp153.dfw.emailsrvr.com ([67.192.241.153]:33703 "EHLO smtp153.dfw.emailsrvr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754028Ab2F3TiM (ORCPT ); Sat, 30 Jun 2012 15:38:12 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 6/30/2012 4:59 AM, Hannes Frederic Sowa wrote: > On Sat, Jun 30, 2012 at 8:17 AM, John wrote: >> diff --git a/Documentation/networking/bonding.txt >> b/Documentation/networking/bonding.txt >> index bfea8a3..5db14fe 100644 >> --- a/Documentation/networking/bonding.txt >> +++ b/Documentation/networking/bonding.txt >> @@ -752,12 +752,22 @@ xmit_hash_policy >> protocol information to generate the hash. >> >> Uses XOR of hardware MAC addresses and IP addresses to >> - generate the hash. The formula is >> + generate the hash. The IPv4 formula is >> >> (((source IP XOR dest IP) AND 0xffff) XOR >> ( source MAC XOR destination MAC )) >> modulo slave count >> >> + The IPv6 forumla is >> + >> + iphash = >> + (source ip quad 2 XOR dest IP quad 2) XOR >> + (source ip quad 3 XOR dest IP quad 3) XOR >> + (source ip quad 4 XOR dest IP quad 4) >> + >> + ((iphash >> 16) XOR (iphash >> 8) XOR iphash) >> + modulo slave count >> + > > Wouldn't it be beneficial to include the ipv6 flow label in the hash > calculation? > > Greetings, > > Hannes > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Hannes, In all of the traffic I inspected I don't believe I saw a single flow label set. Even if it were set 100% of the time by Linux, any packets routed or bridged from another operating system wouldn't see any benefit. The current algorithm distributes the traffic very well, I don't believe adding the flow label would be beneficial even if it were set more frequently. If you feel strongly about its inclusion, though, I am willing to reconsider. John