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 DC03C3CB35 for ; Wed, 18 Apr 2018 12:54:58 -0400 (EDT) Received: by mail-lf0-x236.google.com with SMTP id r125-v6so3659273lfe.2 for ; Wed, 18 Apr 2018 09:54:58 -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=goLU3V2oKysjKYCjBfHcKqIhkmS9x0x3N69b9TosIfY=; b=jVJvB5gwE3n61Qk1TUDBGDQ4wm7R+5F/wUZtq8Z02BZMmkdTnF9F8L9PrMcH+CU56O 1qlYNLoyOz8bEk8XgpSP0I6kYfrQsC+zAvVrMeAG9Tn5sFRogyrIJ7pWLVHYv6SHlMmD vD7n6KHj9Mg/rznaj01e/1L5EY1374AJLNB0j2PcphpUQe97Kw7U8x+uclGyjcP6diMF cYK3jJDa4xt2uxFZPluCoz+gn3spXr2kIQs5ovaC3HQDnJ6tSscc5VRZ71bCq7bknjFs exCLiFsmqO81Nt8KRdB68YEcji6jso4muSMCdKnDhJGDBy//9r/zKtydoJ4afI49nnE7 IT2w== 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=goLU3V2oKysjKYCjBfHcKqIhkmS9x0x3N69b9TosIfY=; b=VbM2CJkbbrMBFDWzXJHm+K5GiRH0lA6yEpoSKE+ccf8QUIcR9hNDayNmWv3a/AfXAH XaCT5n6sxfLbU3uw6VVgSlHAX8qlw0EFTnG+hcV9nJVp1gAg3tbJzkQ418vYgcaUVfLX zUdHM5vQKj9Y8w45Xta2S4kVkezlkrR0ugMTBi6W9Nau72WI4MitLq5PRWtmzH1+jYZb EMnmc4TjKQ5Cl9I2oqPRXAwPPnf4JX1PDuVMPGXhjPv007ISifSLUJIwcvaafVRuf2Lq /8bEv2caQyDPjmaqJ/oMqU38ZyXZa21INDs7y/jTJ6byczteyawxAj4W7j7xzeHq6sq/ 7sxQ== X-Gm-Message-State: ALQs6tAiaMfRICNe44riJnW+dXt678oAH100YfpUQw5Z2fzBFJj7rZeG WkwTQo1azKJBTglXqerLACU= X-Google-Smtp-Source: AIpwx48X4vetZ042U+mO23Dw4SO2tS9vQmQD94I6CiINdgue8DOdNrCJL9LO9cHlN3799Iy3N/dliA== X-Received: by 10.46.153.147 with SMTP id w19mr2007313lji.93.1524070497292; Wed, 18 Apr 2018 09:54:57 -0700 (PDT) Received: from [192.168.239.216] (83-245-234-255-nat-p.elisa-mobile.fi. [83.245.234.255]) by smtp.gmail.com with ESMTPSA id e6-v6sm350073lfg.59.2018.04.18.09.54.51 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 18 Apr 2018 09:54:56 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 11.3 \(3445.6.18\)) From: Jonathan Morton In-Reply-To: <87fu3s1om2.fsf@toke.dk> Date: Wed, 18 Apr 2018 19:54:39 +0300 Cc: Sebastian Moeller , cake@lists.bufferbloat.net Content-Transfer-Encoding: quoted-printable Message-Id: <5BD20E12-2408-4393-8560-3FDA52D86DB3@gmail.com> References: <87vacq419h.fsf@toke.dk> <874lk9533l.fsf@toke.dk> <87604o3get.fsf@toke.dk> <578552B2-5127-451A-AFE8-93AE9BB07368@gmail.com> <87r2nc1taq.fsf@toke.dk> <0BB8B1FD-6A00-49D6-806E-794BD53A449F@gmx.de> <3457DD8E-0292-4802-BD1E-B37771DCADA2@gmail.com> <87fu3s1om2.fsf@toke.dk> To: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= X-Mailer: Apple Mail (2.3445.6.18) Subject: Re: [Cake] A few puzzling Cake results 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: Wed, 18 Apr 2018 16:54:59 -0000 > On 18 Apr, 2018, at 7:11 pm, Toke H=C3=B8iland-J=C3=B8rgensen = wrote: >=20 > What you're saying here is that you basically don't believe there are > any applications where a bulk TCP flow would also want low queueing > latency? :) I'm saying that there's a tradeoff between intra-flow induced latency = and packet loss, and I've chosen 4 MTUs as the operating point. Bear in mind that with high packet loss, the retransmissions take an = extra RTT to complete in any case, and there's a higher probability of = incurring an RTO which will *really* hurt your intra-flow latency. This equation is modified with ECN because a high signalling rate = doesn't result in packet loss or retransmissions, but I'm not presently = making any decisions based on ECN support, except the obvious one of = whether to mark or drop. - Jonathan Morton