From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lj1-x231.google.com (mail-lj1-x231.google.com [IPv6:2a00:1450:4864:20::231]) (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 6F1473B29E for ; Tue, 24 Jul 2018 16:33:48 -0400 (EDT) Received: by mail-lj1-x231.google.com with SMTP id 203-v6so4718328ljj.13 for ; Tue, 24 Jul 2018 13:33:48 -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=Z7TJa5+BuGQ/mRWTK0ytvZg1zODq25io/X+g69n5SN0=; b=e4+fyEOcjh09+Bi7NUW5UuCHjXxJyBVUuoRVlYbDXaCjnTWY7RnD1mGC5pIumbSnoH taSKN22EzF4Y6K2MyN6KcAQQxw4vSucJPXJjIK8QFTMv+mKwfY9XPknAYZlf2KhcWn1q s7rIKqZ/Zi0LKePaG7u5qdr/dDiHR/08dkmq1pkfJGlPOljeMSI+cmz/HjFimRr1GI0R +qMp8Hr1ZDm1iDLCqauJDLS13nabvzh+8Cgr7x23L5RUYqA7H4Gw5ElJLgzBAkO1zTPH 5LpbbWNXgNkZ9WTgEEkaaEqWx1ELjfzK5QVeY7od5NBdGnAAryCWBOP/Bo2/VENBuf1e tPrQ== 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=Z7TJa5+BuGQ/mRWTK0ytvZg1zODq25io/X+g69n5SN0=; b=JOpxTbLtROVPHfmUe5vE4y0DJRvxyKNlFGCKdhAHjFZF9g79aq10PUWy+7XHy/WiS9 pkE852Z0TcEsRNQpIerhEmdDDvlrDUOJpz2b/LCoEogIP/Gd3vTv0sb2PoBav2meaTr8 hRE7218cmy7Cwsgw5kP4qZi5gh+YuHz63FZm9CsPknSSry8+UKhLBMfpDqVrNON4xCzh 9UyHrz7QRXJHpNIRavPWuRzeCXg/zVqkwwAPVgq0BFd9YTvz8/XKJP9gVW1d93BdVN+q rDExUKeWxPnKTsTtiWtRHxOuIGDWU5vYjKlzCielGZHoTEzWN6ZnQP2x6wt7tSPpKYtW grIA== X-Gm-Message-State: AOUpUlE/ZILQwYh197zUpSJcWysejG+G72B8xSPiDCdhO288ydpnETbr IhD/oEPr8FrLOX7Tx8/OIiw= X-Google-Smtp-Source: AAOMgpdNMtFKZdLWf43q8Pvd0qM86GUACzll8KnR1CmmY0Q+jY/PtZbEbb6Q0ZdQwFHK49NANKGFRA== X-Received: by 2002:a2e:6304:: with SMTP id x4-v6mr13911069ljb.9.1532464427313; Tue, 24 Jul 2018 13:33:47 -0700 (PDT) Received: from [192.168.239.216] (83-245-234-9-nat-p.elisa-mobile.fi. [83.245.234.9]) by smtp.gmail.com with ESMTPSA id d6-v6sm1907968lfc.83.2018.07.24.13.33.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jul 2018 13:33:46 -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: Date: Tue, 24 Jul 2018 23:33:45 +0300 Cc: bloat Content-Transfer-Encoding: quoted-printable Message-Id: References: To: Benjamin Cronce X-Mailer: Apple Mail (2.3445.9.1) Subject: Re: [Bloat] No backpressure "shaper"+AQM X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Jul 2018 20:33:48 -0000 > On 24 Jul, 2018, at 11:11 pm, Benjamin Cronce = wrote: >=20 > The problem that I'm getting is by adding my own shaping, a measurable = amount of the benefit of their AQM is lost. While I am limited to Codel, = HFSC+Codel, or FairQ+Codel for now, I am actually doing a worse job of = anti-bufferbloat than my ISP is. Fewer latency spices according to = DSLReports. We do know that applying SQM at the entry to the bottleneck link works = much better than at the exit. It's a fundamental principle. > That's when I thought of a backpressure-less AQM. Instead of having = backpressure and measuring sojourn time as a function of how long it = takes packets to get scheduled, predict an estimated sojourn time based = on the observed rate of flow, but allow packets to immediately vacate = the queue. The AQM would either mark ECN or drop the packet, but never = delay the packet. It's a reasonable idea. The key point is to use a deficit-mode = scheduler/shaper, rather than the credit-mode ones that are common = (mainly TBF/HTB). The latter are why you have such a big, uncontrolled = burst from the ISP in the first place. - Jonathan Morton