From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bifrost.lang.hm (mail.lang.hm [64.81.33.126]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by huchra.bufferbloat.net (Postfix) with ESMTPS id 15D5821F3B4 for ; Thu, 12 Mar 2015 17:54:00 -0700 (PDT) Received: from asgard.lang.hm (asgard.lang.hm [10.0.0.100]) by bifrost.lang.hm (8.13.4/8.13.4/Debian-3) with ESMTP id t2D0rxH8032172; Thu, 12 Mar 2015 16:53:59 -0800 Date: Thu, 12 Mar 2015 17:53:59 -0700 (PDT) From: David Lang X-X-Sender: dlang@asgard.lang.hm To: Dave Taht In-Reply-To: Message-ID: References: <5501B16E.9040207@gmail.com> <1426176829.336613096@apps.rackspace.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: "cerowrt-devel@lists.bufferbloat.net" Subject: Re: [Cerowrt-devel] [Bloat] great interview on the scale conference wifi successes X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Mar 2015 00:54:29 -0000 On Thu, 12 Mar 2015, Dave Taht wrote: > so the wifi and ethernet queues are fq_codeled in this past SCALE. > > One little understood fact about aggregated' wifi is that you CAN > actually FQ the faster rate ethernet queue with the theoretically > slower rate wifi queue, because a wifi aggregate is decoded at memory > speeds, not wire or wireless speeds, and thus, can fill the BQL > ethernet driver queue and have packets stuck at the qdisc layer, where > they can be handled more smartly. > > That said, don't know if that ever happened at scale without data. > > The wifi outgoing interfaces on each AP on the other hand, could very > well have had either the fq or the codel portions of the algorithm > engage... they certainly do on my tests here. > > Although dlang did get quite a lot of data (which I have not yet seen, > or have I had time for - does anyone here have time to analyze it? He > got a ton of minstrel statistics in particular), but I am unsure if he > collected any of the tc -s qdisc data from the wifi interfaces. (?) no, I missed/forgot the request for that. it's about 20G of data uncompressed, I'm running lzma on it now to see how small it will shrink. > I also have to note that the ath9k driver has got so good now, that a > ton of the benefit at scale probably came from that, and a great deal > more, from dlang's excellent design for the network itself. It is sad, > of course, that useful functionality like sta-to-sta transfers has to > be disabled in such environments nowadays. > I am really sorry I couldn't go. > > I am seeing 25% better forwarding rates on ethernet out of 3.18 vs > 3.10 on the same wndr 3800 hardware, btw. hmm, does this have a noticable effect on the HTB throttling performance? David Lang