From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-x244.google.com (mail-lf0-x244.google.com [IPv6:2a00:1450:4010:c07::244]) (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 AF3123B29E for ; Sun, 15 Jul 2018 22:09:41 -0400 (EDT) Received: by mail-lf0-x244.google.com with SMTP id g6-v6so20402399lfb.11 for ; Sun, 15 Jul 2018 19:09:41 -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=PM0lTKhH8gVMH9AP0KbhlysD9MvnaJxLDqeIcpXc9Es=; b=W7dam5ZhP8iCI/sSm1hVjtIFRDwRY4pRBf83vWnWufjGKOJX/Pr7MH4AJieILQW9ud 15k8T9+fSN1rer5OkRDqkYtJtuFko6TxG+K3L1OJEEk+lH87lBSwi+H8fh01nGhFmHrQ olrHnUEvPydXu0jRCdClFjbtsHm+WrkuliSlVqGgkY20tDL49VTQQr3bY5azH+oa6xNA pbfEbVNVHLB+wMwGxK5g05jofFi6YoRCH6zaMu3Qlp+yYNQwdW1M1I3o20W3DpuagBeY eG8ogbipYO4QCK4ZKrrOS+A5hzwFVNnqgcXBg+0Bs4HuHcUmaN+XKVXxj7dx47Qgiddx Livw== 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=PM0lTKhH8gVMH9AP0KbhlysD9MvnaJxLDqeIcpXc9Es=; b=GWG2H6s8IMz3Z1WQCg/hRgT6QUC7PBN4BebiU5wIuJ/DMr9SUAYldeKP/oC41tyjvt fdlbfmWypHL+uQwtFXAlMI11IUBD9Ag387y1hCcquV7TGEUJiLR/k0jK1RXAeYdDNAMk hwNPmjAxasG7a6rAKDLXMyvaDGnl5wFNxDgdMkNmbtbHv9Ok7WAlw5Cwr4UCpr+ZtQ6S gznj9aXry1fBV/ZEl9O6y5DiulDaTNDqpjg+ANGedbWalAJ9kKNxBNSQcKLvusakxHEl M3Pu6OE5+lGQI5gQUaA7fZ8F3icm9nf3wP8toqRXJR9l2jD57YIUQf/rSZKdF0hHXwHo AwEA== X-Gm-Message-State: AOUpUlFzePTcGcHm7xN+S9A023zA49LXyIu/Nm1M7baA+78KpUeJ94dD uTkgITq2Wn4lQAOH/CwLSNstQg+3 X-Google-Smtp-Source: AAOMgpdWCdWi7li4kRTAJSDprvNjRxJlIqcwbQGI+VBirEfwZy7YyDnb2kIzhx7sSX7nU1omGFLnzA== X-Received: by 2002:a19:1003:: with SMTP id f3-v6mr10776752lfi.116.1531706980522; Sun, 15 Jul 2018 19:09:40 -0700 (PDT) Received: from [192.168.239.216] (83-245-233-27-nat-p.elisa-mobile.fi. [83.245.233.27]) by smtp.gmail.com with ESMTPSA id 1-v6sm4591247ljd.11.2018.07.15.19.09.39 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 15 Jul 2018 19:09:39 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.4 \(3445.8.2\)) From: Jonathan Morton In-Reply-To: Date: Mon, 16 Jul 2018 05:09:34 +0300 Cc: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , "cake@lists.bufferbloat.net" Content-Transfer-Encoding: quoted-printable Message-Id: References: <8736wla3lq.fsf@toke.dk> <4C12C6A1-84E3-4B78-885F-F5C212CD13FF@darbyshire-bryant.me.uk> <87wotw96el.fsf@toke.dk> <83B2AEF4-C052-444F-8AFA-E8C3EE2F4A7F@darbyshire-bryant.me.uk> <87wotw6yeo.fsf@toke.dk> To: Kevin Darbyshire-Bryant X-Mailer: Apple Mail (2.3445.8.2) Subject: Re: [Cake] Backporting 'tc class' support 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: Mon, 16 Jul 2018 02:09:42 -0000 > On 16 Jul, 2018, at 1:41 am, Kevin Darbyshire-Bryant = wrote: >=20 > AFAICT the tin order makes no difference whatsoever these days, indeed = the dequeue mechanism picks up from the last tin and spins around rather = than starting at either 0 or highest tin each time. While it might not be entirely apparent from the code, the tin selector = has two-phase behaviour, and this makes the tin ordering important. If *any* tin contains traffic *and* meets its local schedule, the = *highest* such tin is selected unconditionally. Only if *no* such tin = can be found does the search revert to finding the tin with traffic and = with the most-nearly-satisfied schedule. Both conditions are resolved = on a single pass through the tin array. In diffserv3/4, the Best Effort tin is set at the same rate as the = global shaper. Therefore, its local schedule is always met whenever the = global schedule is. Therefore, if it were placed higher in the tin list = than Bulk, it would be able to strictly starve out Bulk traffic, which = is not what I want. Instead I give Bulk the next higher tin and a very = restrictive schedule. - Jonathan Morton