From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-01-iad.dyndns.com (mxout-118-iad.mailhop.org [216.146.32.118]) by lists.bufferbloat.net (Postfix) with ESMTP id 440242E0270 for ; Thu, 24 Feb 2011 15:32:12 -0800 (PST) Received: from scan-01-iad.mailhop.org (scan-01-iad.local [10.150.0.206]) by mail-01-iad.dyndns.com (Postfix) with ESMTP id EE1E46FED1 for ; Thu, 24 Feb 2011 23:31:59 +0000 (UTC) X-Spam-Score: 0.0 () X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 76.96.62.56 Received: from qmta06.westchester.pa.mail.comcast.net (qmta06.westchester.pa.mail.comcast.net [76.96.62.56]) by mail-01-iad.dyndns.com (Postfix) with ESMTP id E16C56F95F for ; Thu, 24 Feb 2011 23:31:58 +0000 (UTC) Received: from omta15.westchester.pa.mail.comcast.net ([76.96.62.87]) by qmta06.westchester.pa.mail.comcast.net with comcast id BzSK1g0031swQuc56zXz3l; Thu, 24 Feb 2011 23:31:59 +0000 Received: from [192.168.1.119] ([98.229.99.32]) by omta15.westchester.pa.mail.comcast.net with comcast id BzXx1g00l0hvpMe3bzXy8J; Thu, 24 Feb 2011 23:31:58 +0000 Message-ID: <4D66EA6C.1030207@freedesktop.org> Date: Thu, 24 Feb 2011 18:31:56 -0500 From: Jim Gettys Organization: Bell Labs User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101208 Lightning/1.0b2 Thunderbird/3.1.7 MIME-Version: 1.0 To: =?UTF-8?B?RGF2ZSBUw6RodA==?= Subject: Re: debloat-testing: Kitten not eaten - was Re: [Bloat] Please enter issues into the issue tracker - Issue system organisation needed. References: <4D6668F4.5010705@freedesktop.org> <4D668827.8060508@freedesktop.org> <1298567313.2814.7.camel@edumazet-laptop> <87sjvds2r7.fsf@cruithne.co.teklibre.org> <4D66E680.3060306@freedesktop.org> <87vd09ja1y.fsf@cruithne.co.teklibre.org> In-Reply-To: <87vd09ja1y.fsf@cruithne.co.teklibre.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Cc: "linville@gmail.com" , bloat-devel@lists.bufferbloat.net 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 Feb 2011 23:32:12 -0000 On 02/24/2011 06:18 PM, Dave Täht wrote: > Jim Gettys writes: > >> On 02/24/2011 01:31 PM, Dave Täht wrote: >> >>> There is a debloat-testing Linux kernel repo up at: >>> >>> http://git.infradead.org/debloat-testing.git >>> >>> It builds, I haven't booted into it yet. The patch set is pretty minor, >>> if you already have a Linux-2.6 tree it pays to use: >>> >>> git clone --references your_existing_tree git://git.infradead.org/debloat-testing.git >>> >>> (Doesn't have SFB yet, either. John?) >> >> I built it; it booted, worked on my eDP display, and did my usual ping >> + scp test (to a local system, so that the 802.11 would be saturated). >> >> OOTB, it controls the latency quite decently (no more than a few >> milliseconds), but the drop rate on the ICMP running at the same time > > This brings the iwl driver down from 130+ms to a few ms!? rtt min/avg/max/mdev = 0.646/3.631/32.951/5.487 ms > > How many more orders of magnitude do you need for *awesome*, rather than decent? Well, we have to do some computation from first principles here. I happened to be running G, so there is about 20Mbps goodput available. If we have 1 packet queued to keep the interface busy all the time, that should insert something like a 1/2 of one millisecond of latency to another flow (if I did my math right). So being in the 3-4ms range is still off by a bit. But we're now much closer to where we should be, that where we started, so consider this major progress. > >> is quite high (~25%). Pretty uncontrolled experiment; my son is home >> ;-). > > That IS high. Perhaps the iwl and the linvilles alg are competing > overmuch. Does your card do aggregation? > No clue; its a iwl6200agn; which is pretty recent; but I was running g. Running n, I'm still getting high icmp (~25%) loss rates; the bandwidth goodput is staying about the same. Then again, it's only running at 54Mbps, so that makes sense. rtt min/avg/max/mdev = 0.671/2.439/6.018/1.411 ms - Jim