From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-la0-x236.google.com (mail-la0-x236.google.com [IPv6:2a00:1450:4010:c03::236]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 624B821F3E4; Thu, 14 May 2015 16:38:05 -0700 (PDT) Received: by laat2 with SMTP id t2so91835265laa.1; Thu, 14 May 2015 16:38:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=mt1GODHTGE099RLZw6XWhkTEzX0Q4LJzrZzvDGqhFYI=; b=PCrlrGqIM5Q4oN5sIYU1aT4Om2SqGkH89lZTvEAFsa63WJdW3NI9NbUJZA8eS21/9V TbrhA6UGVeKvL2DJAlBQLut4HQdEOIgnMWi7lKpVvZMve1Lhb3OCpvNLB8fvUpFERrku 3fiBckPICqhM7tfPYoTDZZedbDGHlbdF2WqMdzfj0f6CB42fifYe9Ngv8X/f8DvHUrVE xL8XEbSjzPK8SPGTXcjcW0LiF+ayizn7lFEPFGBTUqanNkDcbyH3wmqnjCUsP8bZfk7P 4VvVQV1/ZaE8Co/Ufg13FdlPtkfOHqDOI+kZ/iAkkbej7zpzPJjD93QgMsWVIkuhl9Td OT2g== X-Received: by 10.152.234.42 with SMTP id ub10mr4962286lac.60.1431646683962; Thu, 14 May 2015 16:38:03 -0700 (PDT) Received: from bass.home.chromatix.fi (87-93-34-32.bb.dnainternet.fi. [87.93.34.32]) by mx.google.com with ESMTPSA id mx10sm165406lbb.20.2015.05.14.16.38.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 14 May 2015 16:38:03 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) From: Jonathan Morton In-Reply-To: <55552014.2010808@darbyshire-bryant.me.uk> Date: Fri, 15 May 2015 02:37:52 +0300 Content-Transfer-Encoding: quoted-printable Message-Id: References: <55552014.2010808@darbyshire-bryant.me.uk> To: Kevin Darbyshire-Bryant X-Mailer: Apple Mail (2.2098) Cc: cake@lists.bufferbloat.net, bloat Subject: Re: [Bloat] tc -s qdisc questions X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 May 2015 23:38:36 -0000 X-List-Received-Date: Thu, 14 May 2015 23:38:36 -0000 X-List-Received-Date: Thu, 14 May 2015 23:38:36 -0000 X-List-Received-Date: Thu, 14 May 2015 23:38:36 -0000 X-List-Received-Date: Thu, 14 May 2015 23:38:36 -0000 X-List-Received-Date: Thu, 14 May 2015 23:38:36 -0000 > On 15 May, 2015, at 01:22, Kevin Darbyshire-Bryant = wrote: >=20 > 1) Why no ECN marks, only drops? Probably because your hosts are not requesting ECN from servers, and = therefore none of the traffic is ECN enabled. Unfortunately, ECN = requests are disabled by default in most OSes so far, but many servers = will respond to them. On Linux: sysctl net.ipv4.tcp_ecn=3D1 On Windows Vista and later: netsh interface tcp set global ecncapability=3Denabled On MacOS X, you need two commands: sysctl -w net.inet.tcp.ecn_negotiate_in=3D1 sysctl -w net.inet.tcp.ecn_initiate_out=3D1 Once set, Windows will remember it across reboots. Linux and MacOS X = require adding the appropriate entries to /etc/sysctl.conf. > 2) What falls into diffserv class 0 (alias, why has nothing used it? Traffic marked with the CS1 DSCP, which corresponds to =E2=80=9Cbackground= =E2=80=9D. Supposedly BitTorrent is planned to do that, but I haven=E2=80= =99t heard whether it actually does so yet. Application support for = Diffserv is generally poor so far. - Jonathan Morton