From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-x834.google.com (mail-qt1-x834.google.com [IPv6:2607:f8b0:4864:20::834]) (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 454513CB36 for ; Sat, 6 Apr 2019 20:14:09 -0400 (EDT) Received: by mail-qt1-x834.google.com with SMTP id z16so11583618qtn.4 for ; Sat, 06 Apr 2019 17:14:09 -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:cc :content-transfer-encoding; bh=cHH5u9vR6ZCHTQg8wbg9Zu5WPiU4In6CzYIw0R4wLIs=; b=ggZYq8yeoZhzf2iBPPFg04ZmRvDJ/q3ydbyOeA+rXWSU2N4vbxjPhJ0655PDlNlWf9 MQWYjC4AGd0czMOvP4UutUr2fBf1XPBkWMxBNTKa6hMLDEMlpSfTqDCbER2lO08p2evq /JlcD2e4zKYpsVnvfSxH/9RcTpnrNCKmrK9ip9YN9Fyohrh2NtGzjBePiHp1YY497K5F OGQYjUsKcHn5kcgKljDHL6SbAT4L6Q9lkFPF6G0p84QjYoSBLGYO/oZrUiW0MOCH3EoX cFeJQxjm/MuJhkJMsL8tjDQXzZj8BIAex9/8+5q3P3Y04tyqmFcbqsXFVhEbYWyUxYcp FlUA== 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:cc :content-transfer-encoding; bh=cHH5u9vR6ZCHTQg8wbg9Zu5WPiU4In6CzYIw0R4wLIs=; b=gTj/LohvT9fMACddG57v0E0GdqUXTaiNoWR9qMA+UGrzJK936fZ1iEIA8ZSPT30NP/ q6H5rQFRdbqDLYD13KCkIl0vvNEiZmBXqWQDs9ItnQgY2Lmu2ueKBh8Gtj3kCJSCC/lR jPMXjHfWAa8UPQupeHaWqgStWr89KkeDJw9+eUJk0kfRoVcAf1mhMkapE+8DNlogZrWI q5Ia3Wuym8CdH1Z/yOkT0cPVvJ9t16o57K/zlPdFfwnWY22qp2/dqTdwRgl81Ll/ztzj QmXChKIoekMa2CS8v4f2tmpdpkVAcNoezf1fojWQqsqhM+RPCTzBKylk8XN3i2LocHnw PLaA== X-Gm-Message-State: APjAAAVot1DUzgIDwL2UKyKSpizf2/Qsclrn7V6RSxtOEIn/IZMzK9yg mlw6sChtCGx2+zUnwA3TJTENJAqGsxv8X08NNAzQ+Hw5w6Y= X-Google-Smtp-Source: APXvYqyr34joEXED7M+QeS/1iwCnbQof6X+lrLKS4+iBFk/U17+buZ8C8siLXQpaOaU2pbhAcvvpfkZ7g0fdCI+ClK4= X-Received: by 2002:a0c:ea4f:: with SMTP id u15mr17148373qvp.133.1554596048078; Sat, 06 Apr 2019 17:14:08 -0700 (PDT) MIME-Version: 1.0 From: Dave Taht Date: Sun, 7 Apr 2019 02:13:56 +0200 Message-ID: To: Make-Wifi-fast Cc: shawnzhu@umich.edu, zmao@umich.edu Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [Make-wifi-fast] 30+ sec of miserable bufferbloat in wearOS X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 07 Apr 2019 00:14:09 -0000 "When acting as a gateway proxy for a wearable, the phone dramatically inflates the end-to-end (server to wearable) latency to 30+ seconds due to its incurred =E2=80=9Cbufferbloat=E2=80=9D. We then break down the e= nd-to-end latency into various components, and identify the root cause to be the phone-side TCP receive buffer, whose configuration does not take into account the path asymmetry between the wearable-phone path and the phone-server path... " - https://anikravesh.github.io/files/wearos-sigmetrics19.pdf I am of course puzzled as to why they didn't look into sch_cake[1] or fq_codel derived solutions[2], (it is a non-open source OS) but they did manage to eliminate 97% of the problem in their paper, so, there's that. [1] https://arxiv.org/abs/1804.07617 [2] https://www.usenix.org/system/files/conference/atc17/atc17-hoiland-jorg= ensen.pdf --=20 Dave T=C3=A4ht CTO, TekLibre, LLC http://www.teklibre.com Tel: 1-831-205-9740