From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-x132.google.com (mail-lf1-x132.google.com [IPv6:2a00:1450:4864:20::132]) (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 223983CB38; Wed, 11 Dec 2019 15:12:23 -0500 (EST) Received: by mail-lf1-x132.google.com with SMTP id b15so17694345lfc.4; Wed, 11 Dec 2019 12:12:23 -0800 (PST) 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=FOb+Nzx9d4L8DRsrVlE07C4RoWWhGguEGPQAxJyOANM=; b=R/KRurQ3p7XXt4Pny4ZLuGndcv4S2o6335/Wvuaj9V5J91J1Fuf+0fp7ZEfgFyHj+W AB/xMo9meFVG1mPWsRFO2z6zfSEi7lrEkbu7pUcHU3DhbhwRTLdwMCVNIDI9ZYwScdxC Wq+j8y+tEyQlZqypJYCq8s5wWAjUM+U4AkmAs02wS7jTYb9MzayDhr6Sji3f/jOoPQg/ +tF8BTJgVwDak7pFWaym+JYW5fFOAWaKqesUBbMW7iSm5fEJC+XLdKzCZkPpE7/vFrul Rd6l1B0lf9LNPnxm3gm48jMUNCFPv2+C6Dcf43onCqc5wSOD/gCzN0WROaTgSELe6btx 3iQg== 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=FOb+Nzx9d4L8DRsrVlE07C4RoWWhGguEGPQAxJyOANM=; b=R4Av6Jsy4yfDTnaq0WosSXdYGX+3lmQAKxdiPJv8RLrIv6wI3Dnha9TpjmYxNwaRVP Srsu+lxfEDfu7Mf84Uhr0fMwGTUb1OR5EBgYubGfIxp2f6SpQLuBmQ3z+r9Q9wJUz8To YeCtl78KUOj7STzc+XEY1fSbtrChAtUvj73UaooKtMvWJwp5OE2IcwdJsO+2SYJAln+L MIRA5Fn5QDYTvuTr9UZdgeTc9HiAaKQMG47ISCspnEyA2WhLVkv5VTTqZvfq5LVPB6CV yUTuv852xDNxv10c7U1IupNcJXiKg5Q80O/De2B7Fx5ALP8P2RIDikJQzw6zzo6WQyL5 h2tQ== X-Gm-Message-State: APjAAAU9qbMyjgc4VoJsD0iBHIcG7jaKaaCEU827WUANPKkg4j/bAayD jNuLcME/37caMxkkMpMfVlY= X-Google-Smtp-Source: APXvYqwX1eicfsVQaey1myPPK7h9P8I8GnAw0P52jokPgG3obl/npyQJyZRzHhVFrLEJxDAAtPUdSg== X-Received: by 2002:a19:760c:: with SMTP id c12mr3612043lff.60.1576095142075; Wed, 11 Dec 2019 12:12:22 -0800 (PST) Received: from jonathartonsmbp.lan (83-245-229-102-nat-p.elisa-mobile.fi. [83.245.229.102]) by smtp.gmail.com with ESMTPSA id h24sm1722373ljc.84.2019.12.11.12.12.20 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 11 Dec 2019 12:12:21 -0800 (PST) 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: Wed, 11 Dec 2019 22:12:19 +0200 Cc: Prateesh Goyal , Hari Balakrishnan , ECN-Sane , Mohammad Alizadeh , bloat Content-Transfer-Encoding: quoted-printable Message-Id: <2CC1F0FF-4447-4860-BFE6-0C4CA3312953@gmail.com> References: To: Dave Taht X-Mailer: Apple Mail (2.3445.9.1) Subject: Re: [Ecn-sane] [Bloat] abc congestion control on time varying wireless links X-BeenThere: ecn-sane@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussion of explicit congestion notification's impact on the Internet List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Dec 2019 20:12:23 -0000 > On 11 Dec, 2019, at 9:54 pm, Dave Taht wrote: >=20 > The DC folk want a multibit more immediate signal, for which L4S is > kind of targetted, (and SCE also > applies). I haven't seen any data on how well dctcp or SCE -style can > work on wildly RTT varying links as yet, although it's been pitched at > the LTE direction, not at wifi. It turns out that a Codel marking strategy for SCE, with modified = parameters of course, works well for tolerating bursty and aggregating = links. The RED-ramp and step-function strategies do not - and they're = equally bad if the same test scenario is applied to DCTCP or TCP Prague. The difference is not small; switching from RED to Codel improves = goodput from 1/8th to 80% of nominal link capacity, when a rough model = of wifi characteristics is inserted into our usual Internet-path = scenario. We're currently exploring how best to set the extra set of Codel = parameters involved. - Jonathan Morton