From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-x12b.google.com (mail-lf1-x12b.google.com [IPv6:2a00:1450:4864:20::12b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 5B9943B29E; Wed, 19 Sep 2018 02:05:49 -0400 (EDT) Received: by mail-lf1-x12b.google.com with SMTP id m26-v6so4054669lfb.0; Tue, 18 Sep 2018 23:05:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=/TehjPTZoYI9T3BpFpPskkSkuS8PgVAVbh2siUMoO7k=; b=jqkOy8X5Hwx1udYJBukwaizCHASHdjHW72woWRdqUGWR923PxkmKh2BlK7zRATDRwv JHQ/tZgCmDpUTbSFmH7DKBX+ZowuSbD6zhTtxq2NS7oAdhKedcKp9COZiBquGURGL9Va dI+WwVAvFehgRdMyHCsi2Pi4oRKWnJXiO7Rvu7N9bocYKYQhT3XKu3fgLij2VpUeMtig znHXsZe9FXBF+NWMEt+M78E8mlNAruzzmvUTnWU+TwCVS+Jl0xqHH+bfpTUbDJCJ0eKD M4S6Zn6hpBYuboEJywIlYyJIHPVKuIxzZxHGyBbZn+mfkz6t/moEHkyBmLpJjxMVRMFO TxLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=/TehjPTZoYI9T3BpFpPskkSkuS8PgVAVbh2siUMoO7k=; b=a/RgQOrRqTBD+F29ODx+IZKsZ+zGg/8paIWPBQYZ5+y11/DiUVF2B+NmxULzM7z1Be 1qydOCeeCTqIGWqUr+D3OvQ+71IaSl7nB9QqvNF6g0+3maAfFjpP0dqtKVhEHKVd491i i79VttsDDxynHBfDbiySV9LyQkLJYysoV/d7zjisNkVMJnV5gol1MVqoHzsJ/MlWCDpF p/c+3Ips2HGp5Ef/BcCyUMgFkOjePIfsXgbBPKx4Tw1/4V0tKAoJUOo6w4kMdEJ/9sUb C28/mrva8zl6+rRBFg5rATdAm2bOa3m39JiXqAH8//VPAbmtoZS5miXl+mcqMWpETDxJ 0BFg== X-Gm-Message-State: APzg51AFgCilaFChZvD+3XgwjrBfoLec82T1pDNWnA7hXbNPgL8MSK4H 6Sg1sSRm+owq+QLLnG9fIS4= X-Google-Smtp-Source: ANB0VdYJTNqraGCsaSzNv336X58Dd+tcWgcSzCsQ1uZxCpr0HPCwgjje6kev+DAgmurKqYrNISJ+qQ== X-Received: by 2002:a19:988a:: with SMTP id a132-v6mr21176199lfe.76.1537337148033; Tue, 18 Sep 2018 23:05:48 -0700 (PDT) Received: from jonathartonsmbp.lan (83-245-234-249-nat-p.elisa-mobile.fi. [83.245.234.249]) by smtp.gmail.com with ESMTPSA id x3-v6sm3696059ljb.25.2018.09.18.23.05.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 18 Sep 2018 23:05:46 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) From: Jonathan Morton In-Reply-To: <87zhweb9lj.wl-jch@irif.fr> Date: Wed, 19 Sep 2018 09:05:45 +0300 Cc: Dave Taht , Make-Wifi-fast , ecn-sane@lists.bufferbloat.net, babel-users@lists.alioth.debian.org Content-Transfer-Encoding: quoted-printable Message-Id: <7F6B1E4A-7FF1-4AB0-9770-67D18D80BB86@gmail.com> References: <87efdqcs28.wl-jch@irif.fr> <8736u6cpyu.wl-jch@irif.fr> <87zhweb9lj.wl-jch@irif.fr> To: Juliusz Chroboczek X-Mailer: Apple Mail (2.3445.9.1) 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 06:05:49 -0000 > On 19 Sep, 2018, at 3:43 am, Juliusz Chroboczek wrote: >=20 >>> Or perhaps, if we know which queue that is, >>> we could modify Babel's packet scheduling to be more AQM friendly? >=20 >> How would you describe babel's packet schedulig now? >=20 > The main flaw is that it sends periodic updates as a burst of = back-to-back > full-size packets. That could trigger Codel if you had more than 60 > routes or so. >=20 >> So dumping packets in there at a rate no more than 20ms each (short = term >> burst of 100ms) - relative to whatever bandwidth can be achieved vs = the >> other flows. >=20 > Right. Guilty as charged. The general principle you want is pacing, rather than bursting. If you = have a defined refresh interval, spread your routing updates evenly = across that interval. Or pick a rate to send updates at, and use ECN = feedback to adjust that rate. - Jonathan Morton