From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from korolev.univ-paris7.fr (korolev.univ-paris7.fr [IPv6:2001:660:3301:8000::1:2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 06AB43B29E for ; Tue, 18 Sep 2018 20:04:30 -0400 (EDT) Received: from mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [81.194.30.253]) by korolev.univ-paris7.fr (8.14.4/8.14.4/relay1/75695) with ESMTP id w8J04QVW019077; Wed, 19 Sep 2018 02:04:26 +0200 Received: from mailhub.math.univ-paris-diderot.fr (localhost [127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTP id 1F4CCEB200; Wed, 19 Sep 2018 02:04:27 +0200 (CEST) X-Virus-Scanned: amavisd-new at math.univ-paris-diderot.fr Received: from mailhub.math.univ-paris-diderot.fr ([127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id b73ldLUrcyg3; Wed, 19 Sep 2018 02:04:25 +0200 (CEST) Received: from trurl.irif.fr (unknown [78.194.40.74]) (Authenticated sender: jch) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTPSA id 6CF14EB22D; Wed, 19 Sep 2018 02:04:25 +0200 (CEST) Date: Wed, 19 Sep 2018 02:04:25 +0200 Message-ID: <8736u6cpyu.wl-jch@irif.fr> From: Juliusz Chroboczek To: Dave Taht Cc: babel-users@lists.alioth.debian.org, Make-Wifi-fast In-Reply-To: References: <87efdqcs28.wl-jch@irif.fr> User-Agent: Wanderlust/2.15.9 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (korolev.univ-paris7.fr [194.254.61.138]); Wed, 19 Sep 2018 02:04:27 +0200 (CEST) X-Miltered: at korolev with ID 5BA1928A.001 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-j-chkmail-Enveloppe: 5BA1928A.001 from mailhub.math.univ-paris-diderot.fr/mailhub.math.univ-paris-diderot.fr/null/mailhub.math.univ-paris-diderot.fr/ X-j-chkmail-Score: MSGID : 5BA1928A.001 on korolev.univ-paris7.fr : j-chkmail score : . : R=. U=. O=. B=0.000 -> S=0.000 X-j-chkmail-Status: Ham Subject: Re: [Make-wifi-fast] [Babel-users] reducing delays in wifi mcast queues X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Sep 2018 00:04:31 -0000 > Recently I tried to deploy a few babel 1.8.2 nodes with the latest > openwrt, which I had to back out rapidly because I was dropping so many > babel packets under contention. That's interesting. Could I please see a log? > A patch to universally enable babel ecn in net.c "solves" this problem, Interesting. AFAIK, ECN is only considered by AQM queues, so this implies there's a queue in the way that's dropping Babel packets. Perhaps this queue could be convinced to treat Babel packets specially without having to hack around it using ECN? Or perhaps, if we know which queue that is, we could modify Babel's packet scheduling to be more AQM friendly? -- Juliusz