From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-x233.google.com (mail-lb0-x233.google.com [IPv6:2a00:1450:4010:c04::233]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 875E521F424; Thu, 9 Apr 2015 15:02:06 -0700 (PDT) Received: by lbcga7 with SMTP id ga7so621127lbc.1; Thu, 09 Apr 2015 15:02:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=RBv/XfvPU0avsb2eRcG5i21re2U3GoZDZi7jN2cE96I=; b=BzN7zL+7nIqpWiyZlC77PvF9fer3odk7OFscMcnnjXk7tKSNn6j/6XivhaR4H00Nja C6rYhv53VQN4oPhlwK06VZCxR+7AUWjJVXMsYEOPR5Wv2SX0qzXDF75n7jtLJxj4b8vp pdmFFQ+V484+LAOr0ByP+iEi8zMNNdSszyhqoJ/xXcXv8fqP+rtB3Zsn9WwlgFYY2b/U cYzFwn+cetYYK1tfe/BNfk2pNFyHXYZaWcHhN4mSjWaPdLognO0dYjHogInQP3HWLMj5 A3UAQ5xvMJBkpWhIVhQbsWYbLe5Y9f9Dw52ZAqaxegamhPDdSu+Hr1F1Bvi0bKGzyC3v WLxw== X-Received: by 10.112.146.129 with SMTP id tc1mr29465348lbb.27.1428616923902; Thu, 09 Apr 2015 15:02:03 -0700 (PDT) Received: from dhcp204.tdb.fi (tdb.fi. [83.150.90.211]) by mx.google.com with ESMTPSA id i9sm6951lbs.26.2015.04.09.15.02.02 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 09 Apr 2015 15:02:03 -0700 (PDT) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) From: Jonathan Morton In-Reply-To: <67BE685A-724C-45D7-A619-EC49498AF165@gmail.com> Date: Fri, 10 Apr 2015 01:02:00 +0300 Content-Transfer-Encoding: quoted-printable Message-Id: <9A8B9375-C683-4A85-9D65-564AEECE1300@gmail.com> References: <2E760E83-7224-4B9B-B918-B3EAD578E831@gmail.com> <67BE685A-724C-45D7-A619-EC49498AF165@gmail.com> To: Rich Brown X-Mailer: Apple Mail (2.2098) Cc: cerowrt-devel , bloat Subject: Re: [Cerowrt-devel] [Bloat] Questions about the use of HTB & fq_codel in simple.qos, simplest.qos X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Apr 2015 22:02:35 -0000 > On 10 Apr, 2015, at 00:35, Rich Brown wrote: >=20 > - Why do we provide an HTB-based shaper in simple.qos and = simplest.qos? > - Do the shapers in these sqm-scripts actually limit bandwidth for = various kinds of traffic? Might that not leave unused bandwidth? > - Or do they just shunt certain packets to higher or lower priority = fq_codel tiers/bands/levels (terminology used in Dave's note below)? > - And if the latter, how does the "link" (I'm not sure of the proper = term) know which of the tiers/bands/levels to dequeue next? The short answer is: because cake isn=92t out in the real world yet. = We=92re working on it. HTB and IFB as used in those scripts is a stopgap solution, to take = control of the bottleneck queue so that fq_codel can work on it. Cake = includes a shaper which does the job more effectively and more = efficiently. Ultimately, what we=92d like is for fq_codel (or even something as = sophisticated as cake) to be implemented in the *actual* bottleneck = queues, so that artificially taking control of the bottleneck isn=92t = necessary. > I'll state up front that I'm not entirely clear on the distinction = between shapers, qdisc's, IFBs, etc. But I'm groping around for a = simple, clear recommendation for what we should tell people to do so = they can: > a) Make their router work very well, with minimal latency > b) Spend their time more usefully than tweaking QoS/priority = settings (for example, by actually playing the game that whose lag = you're trying to minimize :-) If they=92ve got a router with the sqm-scripts installed, use those and = follow the directions. The implementation is a little messy, but it = works and it keeps things simple for the user. When cake arrives, the implementation will get simpler and more = efficient. - Jonathan Morton