From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ww0-f47.google.com (mail-ww0-f47.google.com [74.125.82.47]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 225AB20016F for ; Thu, 23 Jun 2011 21:33:16 -0700 (PDT) Received: by wwf27 with SMTP id 27so2344174wwf.28 for ; Thu, 23 Jun 2011 22:01:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:subject:from:to:cc:in-reply-to:references :content-type:date:message-id:mime-version:x-mailer :content-transfer-encoding; bh=JHJvrXlOxG5A7C2e//FjOkUvbcJj2/Ovd5bq5Fro6lE=; b=SBl5PCkZdEVINvgR8kcyaFhwX0IA0t1lpEtb6yt231WqqagQopQZpE9sZyEjjpNcyX y2+c0XOOCqgYHPHWfQzB91+7EUZboYng+lTNzmAPgMXfFEbtrw59ZF8VMFghMvid6Mh8 gf8KmRskXs5lpuODfR0YS6Ust5UzsG68aU0qc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=aDlgiACsa4kZ1zlkhgcSe4bki4I+rbkfy8W7o6CEFamyskysUvYWFvYZvjRFUxq8Qf QnZ+16f4vv+SA2e6PSXNVzgot3rd5Vo5GWOkG9ad+bVSh1OyThi7qnUAKgvpyh5K0coT kKmOiMAIjfCmLkQORWrQZAeHoO3QOJAfGzlgs= Received: by 10.216.65.203 with SMTP id f53mr238247wed.54.1308891663152; Thu, 23 Jun 2011 22:01:03 -0700 (PDT) Received: from [10.150.51.213] (gw0.net.jmsp.net [212.23.165.14]) by mx.google.com with ESMTPS id ge4sm1710993wbb.64.2011.06.23.22.01.02 (version=SSLv3 cipher=OTHER); Thu, 23 Jun 2011 22:01:02 -0700 (PDT) From: Eric Dumazet To: Dave Taht In-Reply-To: References: <7ir56kupy8.fsf@lanthane.pps.jussieu.fr> Content-Type: text/plain; charset="UTF-8" Date: Fri, 24 Jun 2011 07:01:00 +0200 Message-ID: <1308891660.3000.7.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 8bit Cc: bloat Subject: Re: [Bloat] Some updates on hacking on AQMS 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, 24 Jun 2011 04:33:17 -0000 Le jeudi 23 juin 2011 à 17:10 -0600, Dave Taht a écrit : > On Thu, Jun 23, 2011 at 4:45 PM, Juliusz Chroboczek wrote: > >> It really seems that ECN support could be added generically for all > >> qdiscs that currently do packet drop. Creating a generic mark_or_drop > >> function is easy. > > > > As hinted in a previous message -- please don't. Every qdisc must be > > examined individually to check if it is suitable for ECN. > > > > Consider also the following. If the administrator specifies a maximum > > rate of 100 Mbit/s, he probably doesn't expect the outgoing traffic to > > exceed that rate under any circumstances. If you start marking instead > > of dropping, you must make sure that the resulting traffic is still > > under 100 Mbit/s, including the marked packets. > > In designing this particular concept I made sure that was an option, > in the mildly recorrected: > > http://www.bufferbloat.net/projects/bloat/wiki/Save_the_Ants > > Try harder to not shoot the ants, but make ecn marking a first class > option throughout the qdiscs... > > if possible.. I believe it was done. qdisc implementations are not random, but follow extensive research works. Before doing a change like that, you must redo all the experiments and show the pro/cons ;) Once qdisc queue is _full_, its too late, you have to drop packets anyway. And its not because at least one flow is not responsive : It might be because one thousand flows began their life at the very same moment :(