Return-path: Received: from mail-wi0-f174.google.com ([209.85.212.174]:62152 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751043Ab3CAV2M (ORCPT ); Fri, 1 Mar 2013 16:28:12 -0500 Received: by mail-wi0-f174.google.com with SMTP id hi8so15915wib.7 for ; Fri, 01 Mar 2013 13:28:11 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20784.48093.263373.125536@gargle.gargle.HOWL> References: <1360329197-72631-1-git-send-email-nbd@openwrt.org> <20757.1753.863278.858198@gargle.gargle.HOWL> <511508A6.8020104@openwrt.org> <51152D9E.1040106@openwrt.org> <20130227192030.GW12537@pogo> <512ECE01.8010102@openwrt.org> <20782.54505.239733.82364@gargle.gargle.HOWL> <512EDDC5.7020901@openwrt.org> <20784.48093.263373.125536@gargle.gargle.HOWL> Date: Fri, 1 Mar 2013 13:28:11 -0800 Message-ID: (sfid-20130301_222816_196634_7AE32D34) Subject: Re: [RFC] ath9k: remove ath9k_rate_control From: Adrian Chadd To: Sujith Manoharan Cc: Felix Fietkau , "Luis R. Rodriguez" , Paul Stewart , linux-wireless Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 1 March 2013 06:31, Sujith Manoharan wrote: > Felix Fietkau wrote: >> What was the distance and what was the rate used? > > A distance of about a meter between the AP and STA. > > AP: DB120 - running an internal build. > STA: WB222 - wireless-testing HEAD. > Signal is about -43 dBm. > Channel 40, HT40- > > I've attached sample runs with minstrel_ht and ath9k-rc. With minstrel_ht, > the numbers fluctuate between 180 and 190 Mbps and the average throughput > varies each time (185, 186 etc.). With ath9k-rc, it's 195+ always. Right. And the reason that it fluctuates is quite likely because at the higher MCS rates (6,7/14,15/22,23) the channel behaviour is not consistent and there's varying levels of packet loss, so things oscillate between a bunch of MCS rates there. IIRC, the ath9k_rc algorithm is a lot more aggressive at sticking to a fixed, working MCS rate. (190mbit TCP on 2-stream? Damn. Looks like I have a little more optimisation to do in FreeBSD. I'm only hitting 160/170mbit TCP on AR9280<->AR9280 and AR9280<->AR9287. But I hit 220-240mbit UDP.) Thanks, Adrian