From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-x236.google.com (mail-lf0-x236.google.com [IPv6:2a00:1450:4010:c07::236]) (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 551F03B2A0 for ; Thu, 2 Jun 2016 11:10:10 -0400 (EDT) Received: by mail-lf0-x236.google.com with SMTP id w16so36060141lfd.2 for ; Thu, 02 Jun 2016 08:10:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=ILSqxGfVyuL1DexC34rk9QyouaPvbRXQ3WGgNgnktkA=; b=eB82TkochupRIujtdjI510x650tB64+1jMBO0MhjQAUM65WMDBS6QP+4KyEOhN58Ce y6CKH+17Yj+I5cxUbGz2EPeIy0+gYVBmAuwwdRkh3wRtT73Zwrtg+lbVaEXCPjsCbB1k 4Fcp2HOiTSkiRqkTpdsdsf+f3N1TCwsWiFDpQxMOm3I/9AXnP8ZCDtelswEq7gpG5Vrd jicRBXfZxTX/M+vPtq1AJTLG2R+UDKEBBG2CsNd1Qw+yFMzXlG3dnkx5J14sS6EQKBqQ kRVFJF/5QU43CDNtwqoelHIv6Mn9OocPWP+I0FkgzeQDvqk16hBko9My5QCP4RFfgfcH PWmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=ILSqxGfVyuL1DexC34rk9QyouaPvbRXQ3WGgNgnktkA=; b=jhgrsS2ZEjOe61wp4cr/r9hM/i1eGLRTN8JINQCjUsl7GJOb648EHhAL1jN82NqFUU UbOpM+txoYFOQfbJznaZfocbKZruERIGj+Ev74lb9+VCVwZU62j10d47m6mUYGYO8rEb 7fbCa6ObORgLIR1bbTwxUI7YaT8EFPMOXWuEAZcOss/FG+SjIDQKjxAAhX60McuHwucy bKWMg2qXjcF7cEhuUGhmx7CuCCQ/Lx6ie/ADs1/leD7LgjOxPH5jEMp7p5pmlUIP25UR JQA9jgw8sVIOOM7Rh1hN7zi1Hbk58psOey/7tErXHQIFNLr82TlA1VjEKevslLxYkgk0 FCJQ== X-Gm-Message-State: ALyK8tKEzSVd4TBkPTKKS1b5+bvc7hnkbkNW6sHK8+gz7fe9nxpoq1BxH5QbcKLk2ZmTPQ== X-Received: by 10.25.154.8 with SMTP id c8mr3454700lfe.135.1464880209067; Thu, 02 Jun 2016 08:10:09 -0700 (PDT) Received: from [192.168.100.11] (37-33-56-85.bb.dnainternet.fi. [37.33.56.85]) by smtp.gmail.com with ESMTPSA id e71sm92781lfg.8.2016.06.02.08.10.07 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 02 Jun 2016 08:10:08 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) From: Jonathan Morton In-Reply-To: <7E9009E9-DB53-4B0E-90F5-5DC3171BEC89@gmx.de> Date: Thu, 2 Jun 2016 18:10:06 +0300 Cc: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , cake@lists.bufferbloat.net Content-Transfer-Encoding: quoted-printable Message-Id: <1A507BE4-35F2-4B09-98C8-915D15EAA641@gmail.com> References: <574FFE52.1040501@darbyshire-bryant.me.uk> <2A84540D-AA30-4BD0-AF9A-5510EA00B7E8@gmail.com> <87a8j3fyxc.fsf@toke.dk> <7E9009E9-DB53-4B0E-90F5-5DC3171BEC89@gmx.de> To: moeller0 X-Mailer: Apple Mail (2.3124) Subject: Re: [Cake] cake/tc - removal of atm/ptm/ethernet specific overhead keywords X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 02 Jun 2016 15:10:10 -0000 > On 2 Jun, 2016, at 17:59, moeller0 wrote: >=20 > As I tried to convey before the matter is far from simple. For example = my ISP, DTAG, has at least 4 different sets of per packet overhead (ATM = versus PTM, BRAS versus BNG) so even for this one ISP there is not one = solution to the issue. And with BRAS/BNG shaping as used by say DTAG the = actual VDLS2 related overhead becomes irrelevant compared to the = overhead setting of that applied policer. I believe trying to simplify = this complexity will lead to false overhead recommendations. I would = rather direct people to better documentation how to deduce the overhead = by measurements and research=E2=80=A6 I think we can make a couple of usefully simplifying assumptions: 1: The encapsulation overhead on the wire is the same in both = directions. 2: The BRAS is irrelevant, because we need to set an ingress qdisc below = the line rate anyway in order to exert control, and the BRAS doesn=E2=80=99= t apply on upload. Does that help at all? - Jonathan Morton