From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lj1-x22f.google.com (mail-lj1-x22f.google.com [IPv6:2a00:1450:4864:20::22f]) (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 DA6103CB35; Sat, 18 May 2019 19:06:25 -0400 (EDT) Received: by mail-lj1-x22f.google.com with SMTP id e13so9230554ljl.11; Sat, 18 May 2019 16:06:25 -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=sqnSpwlcQP0ZLtKv5NRhCrhUlWiic1abvico/m+Ts5c=; b=a3khi2ApsYTaSEYfvrZj/KKjmIq2RNT3mnHmmp6nTt6AMwFel+wKKTRSWNGtQpL7yS c2mzhHF1drfnomuvql0nhrdC5PVfXDkKtEttQTuYfOq6CQ61OQ/F7JxNxQ2MBZfgesfa ePMRpXmkDOQqgOLKXzWg0MUdyZjQQBAkqnLz40PFFJaMYvMnFFTs+9ZkPEzV9qasCwDJ 3rJiwVomOaq99H6nHJQpogFkX60bYZL0XPeHYhokR103+zmh1ayWeuzXUMvh6tM6qgOS P2QfImsuZ4F3SogVL3Qonv1E8c/U8Kwuvr1KaoXdUQWd13alQOWdDCjuV5jP9A46UcwJ 8+TA== 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=sqnSpwlcQP0ZLtKv5NRhCrhUlWiic1abvico/m+Ts5c=; b=B5lakUVlIIyRQUDIBeG8Mb2x8I5lULA07tqHMLruWgp8BjUA6dG1FMDm6lhVdFaN6i QQPQToh08bMEzlr6UqnTyUZRFvj84LYDE8Ip2sgqy3NyXoQQtKx6MHD1vqED1UQBkN1L 5QFu19fyDvRariixJekoSG/Ia73V582hP7tzpZ7cPzbLJj9c/PM26RfOuwPq35++77t+ OHzAIlzEhfW49Z4qgyxc7jKOBCR+wqZY8u/zvZXBOkLg8u0x1cUFGqpoPtE2Igl4GrFj HUgjBIPdc2y8Luu3h++sT31kVYv4Je5885O9wcmMl2Nax3W3hFmOlvQ7U4vcack1iHQP hKTA== X-Gm-Message-State: APjAAAUCH5PCuvvwQ0UZ6PKxoeDxDP0Tk0wJiPkbft3hs3v4PQDPHqRR oJmlpBEBpn7D6LhFeNIxyak= X-Google-Smtp-Source: APXvYqzQu1soGgOBW2/xMfM8i5G0M2Np4w0wT3fvfnSEbAOyR7x6ii6bXwZsywPlQ4aY02AggrC61A== X-Received: by 2002:a2e:548:: with SMTP id 69mr24735227ljf.176.1558220784900; Sat, 18 May 2019 16:06:24 -0700 (PDT) Received: from jonathartonsmbp.lan (85-76-21-226-nat.elisa-mobile.fi. [85.76.21.226]) by smtp.gmail.com with ESMTPSA id d5sm2773952lji.85.2019.05.18.16.06.23 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 18 May 2019 16:06:24 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) From: Jonathan Morton X-Priority: 3 (Normal) In-Reply-To: Date: Sun, 19 May 2019 02:06:23 +0300 Cc: Jonathan Foulkes , Rich Brown , cerowrt-devel , bloat Content-Transfer-Encoding: quoted-printable Message-Id: <328EB0C3-7487-45C7-BD1F-B4C6A329DCC6@gmail.com> References: <2936.1557856670@turing-police> <1557859131.759530583@apps.rackspace.com> <1557871532.754117608@apps.rackspace.com> <87lfz81x7b.fsf@toke.dk> <1557876841.69888745@apps.rackspace.com> <25460D05-4F53-4317-9722-2878B160BD7B@gmx.de> <2D23494F-7B4B-4426-AC57-8CFEA993D60B@jonathanfoulkes.com> <1558219006.29034759@apps.rackspace.com> To: "David P. Reed" X-Mailer: Apple Mail (2.3445.9.1) Subject: Re: [Bloat] (no subject) X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 May 2019 23:06:26 -0000 >> Pardon, but cwnd should NEVER be larger than the number of forwarding = hops between source and destination. >> Kleinrock and students recently proved that the optimum cwnd for both = throughput and minimized latency is achieved when there is one packet or = less in each outbound queue from source to destination (including cross = traffic - meaning other flows sharing the same outbound queue. >=20 > This argument holds only if time-of-flight *between* nodes is = negligible. Trivially, a geosynchronous satellite hop adds only two = nodes but approximately half a second to the one-way path delay, with = potentially thousands of packets existing only as radio waves in the = distance between, not in a queue. Continuing my train of thought, what Kleinrock really implies is that = the cwnd should *exceed* the native BDP by at most the number of hops. - Jonathan Morton