From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f41.google.com (mail-wg0-f41.google.com [74.125.82.41]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 0AAA9200B29 for ; Sun, 6 May 2012 11:15:45 -0700 (PDT) Received: by wgbds1 with SMTP id ds1so2572119wgb.4 for ; Sun, 06 May 2012 11:15:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; bh=lFDbD7GQBSnBMwwt7ZpBG1CalOq5GKYSzP9MZh6ZOMU=; b=qQhMWiXpQSoJyZP4m06rAjd4d0Ltdmz73w1hXLqDl3+FTuwFO1iwdKVaRDB6LrFcfH bNti+4nFGdb0WpmaM0b+ymtLk9GQICqv1evNstSyJgshw7lsEL+XxaFxSqZeOup5rAwo cSyYnzCO++4xAypMAV+GT0UGt4QV37mJkDp8LXkgtaJW9HHSRZjxFMkD+xOEJHUohjgU OMRRZF2qemCIWvf26IdJUoqEZmLyPPNpius1ZbuFw6yR7jrt5+L1JPAAWST6crwx/DK/ 1uK4QPSp5sGe3pswI82d5X5B24AhayYWJN71ZPQFEUXwQiOClIDldBRaewYH4KcEKG6N +1lQ== Received: by 10.180.104.65 with SMTP id gc1mr28878394wib.13.1336328143743; Sun, 06 May 2012 11:15:43 -0700 (PDT) Received: from [172.30.42.18] (122.237.66.86.rev.sfr.net. [86.66.237.122]) by mx.google.com with ESMTPS id u9sm15890963wix.0.2012.05.06.11.15.41 (version=SSLv3 cipher=OTHER); Sun, 06 May 2012 11:15:42 -0700 (PDT) From: Eric Dumazet To: Jim Gettys In-Reply-To: <4FA6B2FB.2030809@freedesktop.org> References: <1336281092.3752.982.camel@edumazet-glaptop> <1336283203.3752.1032.camel@edumazet-glaptop> <1336315913.3752.1598.camel@edumazet-glaptop> <1336324134.3752.1825.camel@edumazet-glaptop> <4FA6B2FB.2030809@freedesktop.org> Content-Type: text/plain; charset="UTF-8" Date: Sun, 06 May 2012 20:15:40 +0200 Message-ID: <1336328140.3752.2014.camel@edumazet-glaptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Cc: codel@lists.bufferbloat.net Subject: Re: [Codel] usage of 'count' in codel X-BeenThere: codel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: CoDel AQM discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 May 2012 18:15:46 -0000 On Sun, 2012-05-06 at 13:20 -0400, Jim Gettys wrote: > I sort of think that having some upper queue time bound makes sense, if > only to ensure that TCP's quadratic (un)responsiveness never gets out of > hand. But we agreed that having an implementation we could play with to > observe reality would likely be better than hand-waving with no > experience about how long the queue should be allowed to grow. Even with normal tcp flows, codel is not responsive enough and too conservative as is. drop_next = control_law(drop_next) with interval/sqrt(count) increments ? Something is _really_ wrong. Thats few drops per second when we need far more than this. interval = 100ms so you need count = 10000 to reach the rate of one drop per ms, regardless of the link capacity. control loop has no input on time of residence of packets.