From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-24-ewr.dyndns.com (mxout-084-ewr.mailhop.org [216.146.33.84]) by lists.bufferbloat.net (Postfix) with ESMTP id E66012E077F for ; Fri, 4 Feb 2011 11:58:36 -0800 (PST) Received: from scan-21-ewr.mailhop.org (scan-21-ewr.local [10.0.141.243]) by mail-24-ewr.dyndns.com (Postfix) with ESMTP id 714BE5CE949 for ; Fri, 4 Feb 2011 19:58:35 +0000 (UTC) X-Spam-Score: 0.1 () X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 75.145.127.229 Received: from gw.co.teklibre.org (75-145-127-229-Colorado.hfc.comcastbusiness.net [75.145.127.229]) by mail-24-ewr.dyndns.com (Postfix) with ESMTP id 8FE2E5CE535 for ; Fri, 4 Feb 2011 19:58:33 +0000 (UTC) Received: from cruithne.co.teklibre.org (unknown [IPv6:2002:4b91:7fe5:2:21c:25ff:fe80:46f9]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "cruithne.co.teklibre.org", Issuer "CA Cert Signing Authority" (verified OK)) by gw.co.teklibre.org (Postfix) with ESMTPS id 131D65E8FF for ; Fri, 4 Feb 2011 12:58:33 -0700 (MST) Received: by cruithne.co.teklibre.org (Postfix, from userid 1000) id AA528121B77; Fri, 4 Feb 2011 12:58:31 -0700 (MST) From: d@taht.net (Dave =?utf-8?Q?T=C3=A4ht?=) To: Juliusz Chroboczek Organization: Teklibre - http://www.teklibre.com References: <87k4hgdte9.fsf@trurl.pps.jussieu.fr> <4D4C05A3.3000901@freedesktop.org> <871v3nemck.fsf_-_@trurl.pps.jussieu.fr> <87r5bnmyi5.fsf@cruithne.co.teklibre.org> <7ihbcj8w8a.fsf@lanthane.pps.jussieu.fr> Date: Fri, 04 Feb 2011 12:58:31 -0700 In-Reply-To: <7ihbcj8w8a.fsf@lanthane.pps.jussieu.fr> (Juliusz Chroboczek's message of "Fri, 04 Feb 2011 19:56:21 +0100") Message-ID: <87vd0zk1w8.fsf@cruithne.co.teklibre.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: bloat@lists.bufferbloat.net Subject: Re: [Bloat] Buffer bloat at the sender 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: Fri, 04 Feb 2011 19:58:37 -0000 Juliusz Chroboczek writes: >> I have been looking over the mq qdisc, > > Do you understand what it's supposed to do? The documentation for it is in the Linux tree under Documentation/networking/multiqueue.txt My understanding is that it is a general purpose mechanism to get traffic into a driver (notably a wireless one) that has multiple queues implemented, in the hope that classified traffic can then line up with one of the more appropriate traffic classifications in the 802.11* standards. [1][2] It does not seem to be widely used at present, and the example in the documentation is overgeneralized and does not hint at this use. There are also all sorts of other interesting hacks^H^H^H^H^H attempts for a reliable delivery/timeliness compromise in the mac layer in the 802.11 standards, including frame aggregation and the like. The latest 802.11* draft is now open for review to IEEE members. [3] How all this stuff interacts in the real world is somewhat undefined. I'm way too far below this level of the stack to care at present, but seeing some scripts that actually tried to wedge wireless udp/tcpip traffic into more appropriate queues at the driver level would be interesting. -- Dave Taht http://nex-6.taht.net [1] http://en.wikipedia.org/wiki/IEEE_802.11e-2005 [2] http://www.intel.com/network/connectivity/resources/doc_library/white_papers/30376201.pdf [3] http://www.ieee802.org/11/