From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-03-ewr.dyndns.com (mxout-106-ewr.mailhop.org [216.146.33.106]) by lists.bufferbloat.net (Postfix) with ESMTP id 3BF8D2E0322 for ; Thu, 24 Mar 2011 06:57:30 -0700 (PDT) Received: from scan-02-ewr.mailhop.org (scan-02-ewr.local [10.0.141.224]) by mail-03-ewr.dyndns.com (Postfix) with ESMTP id 4E770788B63 for ; Thu, 24 Mar 2011 13:57:29 +0000 (UTC) X-Spam-Score: -1.0 (-) X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 209.85.215.43 Received: from mail-ew0-f43.google.com (mail-ew0-f43.google.com [209.85.215.43]) by mail-03-ewr.dyndns.com (Postfix) with ESMTP id C276E788944 for ; Thu, 24 Mar 2011 13:57:28 +0000 (UTC) Received: by ewy20 with SMTP id 20so3122027ewy.16 for ; Thu, 24 Mar 2011 06:57:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:subject:mime-version:content-type:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to:x-mailer; bh=7qUnwDfeXDG1ZpX2nTA3rrQQy4dxNvGkhMt8YMCeJwQ=; b=xD3Vr0qWoyZZyTiq6JduHXmwe3R2mR7d3cPlucmDOVxCOb0jx5bKomt5NNp1vsYtNQ pTwCVLLrc06mylKKKrbNd5f2l6+L3JKtbW0jMS9sZj69ruiZ1H3ZLatxACF1vBKh+Hf8 VwgA6nDcW63iJxi/WLdZVE7Mj/M/yBl+qjraU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; b=KmRHdkwyP98gACnA/qMebgbWOfDtFgqEr56Kgrqe6TLXq8XqS9OcHHIij0nfvcSpL5 wTapo6R5Ihk0aRxWSD4FX+2mIPsSmutqS1VXCvItDVpnbb8OBxV5E5D00O/snBhEFWvR ENkyspJN09Py7Sy8wtK5s1nXSQuAv+3u08oxU= Received: by 10.213.0.207 with SMTP id 15mr351556ebc.20.1300975047941; Thu, 24 Mar 2011 06:57:27 -0700 (PDT) Received: from [192.168.239.42] (xdsl-83-150-84-172.nebulazone.fi [83.150.84.172]) by mx.google.com with ESMTPS id y7sm3031302eeh.21.2011.03.24.06.57.25 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 24 Mar 2011 06:57:26 -0700 (PDT) Subject: Re: [Bloat] Thoughts on Stochastic Fair Blue Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: Jonathan Morton In-Reply-To: Date: Thu, 24 Mar 2011 15:57:23 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <1EC45925-8DE2-4ABA-83AE-09A8E2290100@gmail.com> References: <7imxklz5vu.fsf@lanthane.pps.jussieu.fr> <160809C8-284C-4463-97FE-0E2F03C08589@gmail.com> <1300973556.3747.9.camel@edumazet-laptop> To: Dave Taht X-Mailer: Apple Mail (2.1082) Cc: bloat-devel@lists.bufferbloat.net, Eric Dumazet X-BeenThere: bloat-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: "Developers working on AQM, device drivers, and networking stacks" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Mar 2011 13:57:30 -0000 On 24 Mar, 2011, at 3:44 pm, Dave Taht wrote: >> Here is the POC patch I am currently testing, with a probability to >> "early drop" a packet of one percent per ms (HZ=3D1000 here), only if >> packet stayed at least 4 ms on queue. A fixed time threshold doesn't take into account the wildly varying = bandwidths of connections. For example, 4ms will cause almost any = queued packet on a 33.6K modem uplink (or a 3G or GSM tether) to be = marked, yet with the 128-packet default size for SFQ, a GigE NIC will = typically empty the queue before any packets reach the marking = threshold. But perhaps a heuristic such as not marking packets which are the last = in their bucket would be okay, and mark everything else when the queue = is more than half full. - Jonathan