From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-x22a.google.com (mail-lb0-x22a.google.com [IPv6:2a00:1450:4010:c04::22a]) by lists.bufferbloat.net (Postfix) with ESMTPS id 308253ED42 for ; Wed, 23 Dec 2015 08:06:33 -0500 (EST) Received: by mail-lb0-x22a.google.com with SMTP id pv2so60461358lbb.1 for ; Wed, 23 Dec 2015 05:06:33 -0800 (PST) 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=gVvPLLxwdMfbNvpKOBWOvVFAMN3l2XYWlZ23sUUUj3M=; b=FypfzmdsclvRFVtKn589Vi6wTnjxJCTCpu4PefPIRC6yS0ehy9oTspNhTRq20DkzaW RaUWcvtw4Ko2qvIb0RChJYol9eI9Fm9fk/DJk3xMG8Ah6lB5WSLUaz1QqRGP+ncCHCU/ cKb1SyuwkALrfJ0NDm9ka9GRodarLcmhQyk4Hx5wnCcw6ap0BF/cQ8pP1IWRwsqFv55x aC/dHCsYjWXzLbP8uYeC2as4foxNU7FThr5aq8kAgPwxmlGnZaWH5GKxeINy1jr1gYdB hduCgh8zFhRRGRNjSsst7VeI4RRj3e47Hen9gwM5M2oS3XO+fNhKFmzHj4ttWBh73kZP 1TFw== X-Received: by 10.112.129.134 with SMTP id nw6mr10473383lbb.10.1450875991886; Wed, 23 Dec 2015 05:06:31 -0800 (PST) Received: from bass.home.chromatix.fi (37-33-99-74.bb.dnainternet.fi. [37.33.99.74]) by smtp.gmail.com with ESMTPSA id d203sm6595528lfg.39.2015.12.23.05.06.30 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 23 Dec 2015 05:06:31 -0800 (PST) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.2 \(3112\)) From: Jonathan Morton In-Reply-To: Date: Wed, 23 Dec 2015 15:06:28 +0200 Cc: Kevin Darbyshire-Bryant , moeller0 , cake@lists.bufferbloat.net Content-Transfer-Encoding: quoted-printable Message-Id: <021986E5-5915-4D60-A391-6C6151AA6EBC@gmail.com> References: <6F86FBB0-AA69-44F3-82D0-31465906974D@gmx.de> <56657A82.2080601@darbyshire-bryant.me.uk> <95560E7E-DEAF-40D8-B704-CEA38A0CDE62@gmx.de> <85A5A21C-E468-4F81-8A36-0F1AD6C84435@gmx.de> <5679CF0F.4080506@darbyshire-bryant.me.uk> To: Dave Taht X-Mailer: Apple Mail (2.3112) Subject: Re: [Cake] second system syndrome 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, 23 Dec 2015 13:06:33 -0000 > On 23 Dec, 2015, at 14:41, Dave Taht wrote: >=20 > Are you actually testing your codel changes at longer RTTs? The latest set has, so far, only been tested on an ordinary Internet = link. It produced an immediately noticeable improvement on ingress = there, implying that it=E2=80=99s controlling the upstream queue better. I=E2=80=99m reasonably confident, however, that it=E2=80=99ll stand up = to more varied tests as well. Fundamentally, it returns to the standard = Codel trigger mechanism under most circumstances, since that=E2=80=99s = been shown to work well. It also adds a new wrinkle that only appears when the queue is growing = very quickly, to trigger the signalling early when it=E2=80=99s = abundantly clear that it *will* inevitably trigger later. I think this = will particularly help cope with TCP slow-start or, on a long-RTT path, = with RTT-independent TCPs like CUBIC. Feel free to run your own tests. I need to sleep. - Jonathan Morton=