From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-x231.google.com (mail-wr0-x231.google.com [IPv6:2a00:1450:400c:c0c::231]) (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 CBF473B2A3 for ; Wed, 22 Feb 2017 05:17:15 -0500 (EST) Received: by mail-wr0-x231.google.com with SMTP id z61so4832501wrc.1 for ; Wed, 22 Feb 2017 02:17:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:content-transfer-encoding:subject:message-id:date:to :mime-version; bh=KC7n0ozojTCZOy1jE++5CD6eBMNiSen3y+D4TnOOlXw=; b=cpTP6cK6oVBjQeU7SA1+CPiohMMibJ7gsYeFfJ6hpH0SwM7v+PGo1kldJUqNjuwsVX eYPTz6q8vZOTk1wmOcoKrRAzZSL+BCH7U3Rg2fg4O3bAFQP9JQNnGdjaMffMibpHZ7rd zOflNHDOYQcXbG8akW11Dzi87Hok+FLdu4sJsUbMOuiR1+03zW+gailG3DObDIpo58yW ZPw7vKb/ouWG2KD1X1uu3DFzxGDCHFNulM9S51rhDKgYzz/L5BV0Muk2Aj61XjaON4wQ zLt0TPy/xr/ltk6qqOyNJdH8Zcm11gbJLZJN2CoUgJCFP2XC1AAyrqqqqgZf9lMDFlgN XNtA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:content-transfer-encoding:subject :message-id:date:to:mime-version; bh=KC7n0ozojTCZOy1jE++5CD6eBMNiSen3y+D4TnOOlXw=; b=kHFHX2ViFaRHnjBAib/LS/ErRoCIoSB1Otnpxc+xsynXBcc5ANPb2l3XslKE2hsGEr givJSIrtQEaHb3Dcha4a5R7g6mgtoxtIPcPvr5trW8Jsr7WOh/DtoRNGpJCpyB26+hEu z916ZXJY6yf9LGzWTqpqc7suldTHtQPOSI/detM1SbvBInV2NXh22C4WwrA0tJhfOSp6 efTnkSU62w23rFsew1ZwMUjDmZ8lZsFifFgMllL/veKq9m1eM26t9A3kaV9URJniNepn AxBI8XdwPsHbj/mH8IuBIRXsLDKaBklbB/xc8yGuRpucK2L2Tx0UBK5pOhRltvZ9zD8K yhCw== X-Gm-Message-State: AMke39m2aIRkeSZpb/WF6hkjqdu2hTF4dO81XsGq6H6JWBoXz6iReQCJ+QCPMMKmJ59S7g== X-Received: by 10.223.171.66 with SMTP id r2mr22591685wrc.71.1487758634099; Wed, 22 Feb 2017 02:17:14 -0800 (PST) Received: from [10.72.0.41] (h-1169.lbcfree.net. [185.99.119.68]) by smtp.gmail.com with ESMTPSA id w204sm1450446wmd.17.2017.02.22.02.17.13 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 22 Feb 2017 02:17:13 -0800 (PST) From: Pete Heist Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Message-Id: Date: Wed, 22 Feb 2017 11:17:11 +0100 To: cake@lists.bufferbloat.net Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) X-Mailer: Apple Mail (2.3124) Subject: [Cake] diffserv3 tin 2 target 50% of interval? 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, 22 Feb 2017 10:17:16 -0000 Hi, I=E2=80=99m finally getting to diffserv testing and am wondering = about the tin 2 parameters of the default =E2=80=98diffserv3': Tin 0 Tin 1 Tin 2 =20 thresh 3125Kbit 50Mbit 12500Kbit target 5.8ms 5.0ms 5.0ms interval 100.8ms 100.0ms 10.0ms Pk-delay 0us 0us 0us Av-delay 0us 0us 0us Sp-delay 0us 0us 0us =E2=80=A6 My understanding from the latest CoDel RFC: = https://www.ietf.org/id/draft-ietf-aqm-codel-06.txt and notes in the Overview section of this document from K. Nichols: = http://www.pollere.net/Pdfdocs/noteburstymacs.pdf are that =E2=80=98interval' should generally remain at 100ms and that = =E2=80=98target' should be computed at around 5-10% of interval, and = preferably closer to 5%. In my testing, which I=E2=80=99ll release more results from soon, I=E2=80=99= ve seen no significant benefit to changing target or interval from their = defaults for either Wi-Fi or 100Mbit wired links. I question that = lowering tin 2=E2=80=99s interval to 10ms provides any benefit, and in = fact could very well cause undesired behavior for those using the = defaults. I could provide a spread of tests comparing =E2=80=98diffserv3' to = =E2=80=98diffserv4=E2=80=99 for rrul at various bandwidths, but since = =E2=80=98diffserv4=E2=80=99s tins all have standard 5/100 target and = interval parameters, that seems preferable to the default of = =E2=80=98diffserv3=E2=80=99. Is there a justification for setting the = interval outside the guidelines suggested by CoDel=E2=80=99s authors? Pete