From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it1-x12b.google.com (mail-it1-x12b.google.com [IPv6:2607:f8b0:4864:20::12b]) (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 447833B2A4 for ; Wed, 29 May 2019 11:05:36 -0400 (EDT) Received: by mail-it1-x12b.google.com with SMTP id 9so4093244itf.4 for ; Wed, 29 May 2019 08:05:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to :content-transfer-encoding; bh=Dk14dFio48Eipa4uwZVKGYEs70qIKjbGNu3Bl3L0oEg=; b=UTZXewN49kq69a+5eEPd98vtb5SDVTV0UFb1xEmZx86F6f259qpuLPXqLiyZQhGS1p JbzILtEZxReG1J+Sjo5cD42cR91kjLH7E2f4PeeXjjwSjBGqGmOIoXIGHi7kBMXfWh0p 3K6bfBvB91DkKv5/A7V8bOSqPQ8Lt4DFll3+wJV1CHzM9ONVNUkYpRs9rl0IssZ0O586 cnkhx5VfenF7frKHr3R5k5MPqYGckZYj+1QAil7UIkRaAkSNX5ivetBF+6D7CwcMdfey DXZP3QAMV/e0Rn05NOhHAjGIbCD4JX1E1uv13XPxOvZV2lnjaG45mrk2oEt8LbCwHBli BdFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to :content-transfer-encoding; bh=Dk14dFio48Eipa4uwZVKGYEs70qIKjbGNu3Bl3L0oEg=; b=T0S7kbdFPBSRIPQpeeDUiZRMb5wvP8fN4Ds8lwe+CbqORufuN8UdnBaWssKloX8VfT RCReaaEryu/JgpBufBD/NEK0/7aYqmkqxjCAAJ5sjz+wDYqPdE4dD9tM5nHPTe+PLPV1 xm7u4zilllebGCvD2f0qEjja/bJ6ReqFWzp6bXHwfND61GbN5mn8uE867IC1oGu99nyA 0O0D3lcqxcYwyxnTAdL4j0VEv9/slWmTze6QEBkyU+5hnmJyWNbGpGD4iL8VIvlJm1zP LrfOH7Z3E9YGv/axhtI8BnCmqq17FSktSZ3ju+YIAtTg3gE+ppKNsahmffTF/VJMTrNN CMsQ== X-Gm-Message-State: APjAAAXK/71sWS4RdKLzKfPNR9ZxTH4g3UbVKPq3RCkNd/G71MnRrHme pLbR1lwHTlNitKuvpEi52oUV/L7uAiWorRZOzvA= X-Google-Smtp-Source: APXvYqzoCA6Kk+0Bbk9lkv/V1CksR4H3Dy0pccpmiuRq7KootArxpM5xDiHHcjmBZU7/GVG0Qvj7i1LwRCkEEI240QM= X-Received: by 2002:a24:ac0a:: with SMTP id s10mr8633551ite.60.1559142335581; Wed, 29 May 2019 08:05:35 -0700 (PDT) MIME-Version: 1.0 From: Dave Taht Date: Wed, 29 May 2019 08:05:24 -0700 Message-ID: To: BBR Development , bloat Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [Bloat] BBR high RTT unfairness: Fifty Shades of Congestion Control: A Performance and Interactions Evaluation 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: Wed, 29 May 2019 15:05:36 -0000 I have been trying to work through this paper: https://arxiv.org/pdf/1903.03852.pdf which is enormous and well worth reading. I have a theory, though, about TABLE XII, which contrasts four BBR flows at different RTTs, in that BBRv1's probe phase makes a 200ms assumption, thus not seeing the real rtt at ong rtts, and thus the longest RTT flow gets the most bandwidth on this test, and the second (testable) theory is that were these rtts not exactly on the 100ms boundaries, we would see more throughput fairness. and thus we end up with the tput BBR(100ms) 0.94 95.90 1.02 1.02 0.62 BBR(200ms) 2.36 95.89 2.53 2.48 BBR(300ms) 1.09 95.89 1.20 1.14 BBR(400ms) 4.57 95.89 4.79 4.59 --=20 Dave T=C3=A4ht CTO, TekLibre, LLC http://www.teklibre.com Tel: 1-831-205-9740