From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1-ext.rs.github.com (smtp1-ext.rs.github.com [207.97.227.250]) by huchra.bufferbloat.net (Postfix) with ESMTP id 209FF2012F7 for ; Sun, 8 Jul 2012 11:24:50 -0700 (PDT) Received: from github.com (sh2.rs.github.com [50.57.128.197]) by smtp1-ext.rs.github.com (Postfix) with ESMTP id 3F4644280B for ; Sun, 8 Jul 2012 11:24:47 -0700 (PDT) Date: Sun, 08 Jul 2012 11:24:47 -0700 From: GitHub To: cerowrt-commits@lists.bufferbloat.net Message-ID: <4ff9d06f2f38c_39ff1082af4104881@sh2.rs.github.com.mail> Subject: [dtaht/ceropackages-3.3] b142be: Added babelm branch which contains a new smoothed ... Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="--==_mimepart_4ff9d06f2c55f_39ff1082af4104642"; charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: cerowrt-commits@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list Reply-To: GitHub List-Id: Development commits for the cerowrt project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Jul 2012 18:24:50 -0000 ----==_mimepart_4ff9d06f2c55f_39ff1082af4104642 Date: Sun, 08 Jul 2012 11:24:47 -0700 Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-ID: <4ff9d06f2dedf_39ff1082af41047e6@sh2.rs.github.com.mail> Branch: refs/heads/master Home: https://github.com/dtaht/ceropackages-3.3 Commit: b142be5189554e29f3a93f6ff36674aa57315260 https://github.com/dtaht/ceropackages-3.3/commit/b142be5189554e29f3a93f6ff36674aa57315260 Author: Dave Taht Date: 2012-07-08 (Sun, 08 Jul 2012) Changed paths: A net/babelm/Makefile A net/babelm/files/babeld.conf A net/babelm/files/babeld.config A net/babelm/files/babeld.init A net/babelm/patches/0001-Mark-packets-as-ECN-capable.patch R net/babelz/Makefile R net/babelz/files/babeld.conf R net/babelz/files/babeld.config R net/babelz/files/babeld.init R net/babelz/patches/0001-Mark-packets-as-ECN-capable.patch Log Message: ----------- Added babelm branch which contains a new smoothed metric algo I note that this experimental package also contains a patch to mark babel packets as ECN capable, when in reality they are not, at present. In the words of Juliusz: "that's a horrible kludge. You're applying AQM to locally-originated data in order to compensate for the lack of backpressure, and then falsely asserting ECN in order to bypass the AQM policy." As for the first statement, queues are necessary at multiple layers in the stack, so I can think of no effective means of supplying backpressure at insertion time that will work. I can think of means of supplying congestion related drop indications to babel, but that is as yet, unimplemented. As to the second objection, yes this is bypassing AQM policy, however, at some point, using ECN marking in babel could be used for something. The udp markings can be easily obtained with pktinfo in userspace, and I do need to produce a patch for that. In the interim, the problem I am trying to solve is that when a rate change happens in wifi, it is abrupt and can take a long time (with the fq_codel aqm rapidly ramping up packet drop) to drop the backlog back to a normal level for the new rate. IMHO it is better to have a radio continue to function rather that potentially stop entirely because it dropped a bunch of babel packets while seeking a new equilibrium. ----==_mimepart_4ff9d06f2c55f_39ff1082af4104642--