From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-x22f.google.com (mail-wi0-x22f.google.com [IPv6:2a00:1450:400c:c05::22f]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 16AB021F303 for ; Sun, 2 Mar 2014 13:41:36 -0800 (PST) Received: by mail-wi0-f175.google.com with SMTP id hm4so2595146wib.14 for ; Sun, 02 Mar 2014 13:41:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=YrT7LfBgbfxEFxrlFNftFusCd+XksICP6B+Kx9Ym5qE=; b=L7bXTclMD4zulK6eE/5S33kZJpTu11L9JJ8Xf1RJ7BCxm5pbIDpBrZou2oagZcnywY q7vpw6WfbbTaFNKvzFoD4sfPjkyPC1o7aFgsjBEW8Wdydk09BrNWHvnuqpNWfopyBfSV eEeBRXbTFxgaFCsVq0GBmKE5yWe6upkS/Cn5xF9lbOg5dcAczUI5xBVmrExEG5Ps1yQe CSgmKgSGYnRNSaWYOBHHedchBDkNL9sXX7C66qpN3DoF0LbjwNpWVNgmPNdjZxJLE0St 16thTuRlIFQB+CKtG+395418ab4zg3r7ReWfUvuoXix7nTEr6DHPd8+b2qgF/lo+qmzO +Z9Q== MIME-Version: 1.0 X-Received: by 10.180.189.169 with SMTP id gj9mr12242372wic.17.1393796495146; Sun, 02 Mar 2014 13:41:35 -0800 (PST) Received: by 10.216.8.1 with HTTP; Sun, 2 Mar 2014 13:41:35 -0800 (PST) In-Reply-To: <5EC471C4-64B9-4D83-AB78-5219E2090886@gmail.com> References: <5EC471C4-64B9-4D83-AB78-5219E2090886@gmail.com> Date: Sun, 2 Mar 2014 13:41:35 -0800 Message-ID: From: Dave Taht To: Rich Brown Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: cerowrt-devel Subject: Re: [Cerowrt-devel] Better results from CeroWrt 3.10.28-16 X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 02 Mar 2014 21:41:37 -0000 Nice work! I have a problem in that I can't remember if target autotuning made it into that release or not. Coulde you do a tc -s qdisc show dev ge00 on your favorite of the above and paste? I still think target is still too low on the egress side with the current calculation. Secondly, now that you have a setting you like, trying pie, codel, and ns2_codel also would be interesting. efq_codel is currently uninteresting. Wasn't clear if you were using nfq_codel or fq_codel throughout. On Sun, Mar 2, 2014 at 1:18 PM, Rich Brown wrote: > I took some time this weekend, and ran careful speed and latency tests on= the CeroWrt 3.10.28-16 build. I have a much better understanding of how al= l this works, both in theory and in practice. Here's an executive summary o= f the overall test procedure with lots of details below. > > Adjusting CeroWrt's configured up- and download rates in the SQM page aff= ects both the actual data transfer rates as well as the latency. If you set= the values too low, CeroWrt will enforce that bottleneck, and the transfer= rates will be lower than you could attain on your link. If you configure t= hem too high, though, the transfer rates may look better, but the latency c= an go off the charts. Here's how I arrived at a good balance. > > Test Conditions: > > - Running tests from my MacBook Pro, 10.9.2. > - Wi-Fi off; ethernet cable direct to Netgear WNDR3700v2 with CeroWrt 3.1= 0.28-16. > - DSL service from Fairpoint, nominally "7 Mbps down/768kbps up". > - DSL Modem sync rate (the actual rate that bits enter/leave my house) is= 7616kbps down; 864kbps up. The line is apparently fairly clean, too. > - Base ping time to the nearest router at ISP (via traceroute) is 29-30 m= sec. > - To minimize other traffic, I turned off most of the computers at home, = and also quit my mail client (which is surprisingly chatty). > > The Tests: > > I ran two different tests: netperf-wrapper with the RRUL test, and speedt= est.net. These give very different views of performance. RRUL really stress= es the line using multiple simultaneous up and download streams. Speedtest.= net is a consumer test that only tests one direction at a time, and for a s= hort time. We want to look good with both. > > For the RRUL tests, I invoked netperf-wrapper like this: netperf-wrapper = rrul -p all_scaled -l 60 -H atl.richb-hanover.com -t text-shown-in-chart > For the Speedtest.net tests, I used their web GUI in the obvious way. > > For both tests, I used a script (pingstats.sh, see my next message) to co= llect the ping times and give min, max, average, median, and 10th and 90th = percentile readings. > > Test Procedure: > > I ran a series of tests starting with the up/down link rates spelled out = by Sebastian Moeller's amazingly detailed note last week. See https://lists= .bufferbloat.net/pipermail/cerowrt-devel/2014-February/002375.html Read it = carefully. There's a lot of insight available there. > > The initial configuration was 6089/737 down/up, with the (nearly default)= values for Queue Discipline (nfq_codel, simple.qos, ECN on for ingress; NO= ECN for egress, auto for both ingress and egress latency targets), and ATM = link layer with 44 bytes of overhead. > > With those initial configuration values, latency was good but the speeds = were disappointing. I then re-ran the tests with CeroWrt configured for hig= her up/down link speeds to see where things broke. > > Things got better and better with increasing link rates until I hit 7600/= 850 - at that point, latency began to get quite large. (Of course, with SQM= disabled, the latency got dreadful.) > > There was an anomaly at 7000/800 kbps. The 90th percentile and max number= s jumped up quite a lot, but went *down* for the next test in the sequence = when I increased the upload speed to 7000/830. I ran the experiment twice t= o confirm that behavior. > > I should also note that in the course of the experiment, I re-ran many of= these tests. Although I did not document each of the runs, the results (sp= eedtest.net rates and the pingstats.sh values) were quite consistent and re= peatable. > > Conclusion: > > I'm running with CeroWrt 3.10.28-16 configured for down/up 7000/830, (nea= rly) default Queue Discipline and ATM+44 bytes of overhead. With these conf= igurations, latency is well in hand and my network is pretty speedy. > > We need to figure out how to explain to people what to expect re: the tra= deoff between "faster speeds" that show up in Speedtest.net (with accompany= ing crappy performance) and slightly slower speeds with a *way* better expe= rience. > > The data follows... > > Rich > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > RRUL Tests: The charts associated with these RRUL runs are all available= at http://richb-hanover.com/rrul-tests-cerowrt-3-10-28-16/ > > 6089/737: > Min: 28.936 10pct: 29.094 Avg: 40.529 Median: 37.961 90pct: 52.63= 6 Max: 77.171 Num pings: 77 > > 6200/750: > Min: 28.715 10pct: 29.298 Avg: 41.805 Median: 39.826 90pct: 57.41= 4 Max: 72.363 Num pings: 77 > > 6400/800: > Min: 28.706 10pct: 29.119 Avg: 39.598 Median: 38.428 90pct: 52.35= 1 Max: 69.492 Num pings: 78 > > 6600/830: > Min: 28.485 10pct: 29.114 Avg: 41.708 Median: 39.753 90pct: 57.55= 2 Max: 87.328 Num pings: 77 > > 7000/800: > Min: 28.570 10pct: 29.180 Avg: 46.245 Median: 42.684 90pct: 62.37= 6 Max: 169.991 Num pings: 77 > Min: 28.775 10pct: 29.226 Avg: 43.628 Median: 40.446 90pct: 60.21= 6 Max: 121.334 Num pings: 76 (2nd run) > > 7000/830: > Min: 28.942 10pct: 29.285 Avg: 44.283 Median: 45.318 90pct: 58.00= 2 Max: 85.035 Num pings: 78 > Min: 28.951 10pct: 29.479 Avg: 43.182 Median: 41.000 90pct: 57.57= 0 Max: 74.964 Num pings: 76 (2nd run) > > 7600/850: > Min: 28.756 10pct: 29.078 Avg: 55.426 Median: 46.063 90pct: 81.84= 7 Max: 277.807 Num pings: 84 > > SQM Disabled: > Min: 28.665 10pct: 29.062 Avg: 1802.521 Median: 2051.276 90pct: 2= 762.941 Max: 4217.644 Num pings: 78 > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > Speedtest.net: First values are the reported down/up rates in the Speedte= st GUI > > 6089/737: > 5.00/0.58 > Min: 28.709 10pct: 28.935 Avg: 33.416 Median: 31.619 90pct: 38.60= 8 Max: 49.193 Num pings: 45 > > 6200/750: > 5.08/0.58 > Min: 28.759 10pct: 29.055 Avg: 33.974 Median: 32.584 90pct: 41.93= 8 Max: 46.605 Num pings: 44 > > 6400/800: > 5.24/0.60 > Min: 28.447 10pct: 28.826 Avg: 34.675 Median: 31.155 90pct: 41.28= 5 Max: 81.503 Num pings: 43 > > 6600/830: > 5.41/0.65 > Min: 28.868 10pct: 29.053 Avg: 35.158 Median: 32.928 90pct: 44.09= 9 Max: 51.571 Num pings: 44 > > 7000/800: > 5.73/0.62 > Min: 28.359 10pct: 28.841 Avg: 35.205 Median: 33.620 90pct: 43.73= 5 Max: 54.812 Num pings: 44 > > 7000/830: > 5.74/0.65 (5.71/0.62 second run) > Min: 28.605 10pct: 29.055 Avg: 34.945 Median: 31.773 90pct: 42.64= 5 Max: 54.077 Num pings: 44 > Min: 28.649 10pct: 28.820 Avg: 34.866 Median: 32.398 90pct: 43.53= 3 Max: 69.288 Num pings: 56 (2nd run) > > 7600/850: > 6.20/0.67 > Min: 28.835 10pct: 28.963 Avg: 36.253 Median: 34.912 90pct: 44.65= 9 Max: 54.023 Num pings: 48 > > SQM Disabled: > 6.46/0.73 > Min: 28.452 10pct: 28.872 Avg: 303.754 Median: 173.498 90pct: 499= .678 Max: 1799.814 Num pings: 45 > _______________________________________________ > Cerowrt-devel mailing list > Cerowrt-devel@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cerowrt-devel --=20 Dave T=E4ht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.= html