From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.17.20]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mout.gmx.net", Issuer "TeleSec ServerPass DE-1" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id D906E21F2CE for ; Tue, 21 Oct 2014 00:51:07 -0700 (PDT) Received: from hms-beagle.lan ([134.2.89.70]) by mail.gmx.com (mrgmx101) with ESMTPSA (Nemesis) id 0LfGo0-1YVFMu3yiu-00onr9; Tue, 21 Oct 2014 09:51:05 +0200 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Sebastian Moeller In-Reply-To: Date: Tue, 21 Oct 2014 09:51:05 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <48166E57-0CCF-48E7-901B-6EF372F59663@gmx.de> References: <7B5DD5A3-D273-4708-909C-5B5D5DE72282@gmx.de> <440DFB9A-C4F8-4723-A407-20ABDBB7BD09@gmx.de> To: =?windows-1252?Q?Dave_T=E4ht?= X-Mailer: Apple Mail (2.1878.6) X-Provags-ID: V03:K0:VfjutfqjxktKTztWlAtENFy0XqsotvdcNLwExMrX1IFmjnvauHY y18Trj/r1A651SCMfEKX+KdEY5mInIDIYOAvi+b5y53Pl9HAH9gRVEqKdJyUfNlDevJVepA GBjLGxPEsM+6g42WelmJfF8kJY0oat/Xy0XxEFdVpS/jtSwC1QOSVdx13ArKBZEbssn2TZf RfIlwFis9Daz8ZQTN4VCw== X-UI-Out-Filterresults: notjunk:1; Cc: cerowrt-devel Subject: Re: [Cerowrt-devel] Routing limit question 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: Tue, 21 Oct 2014 07:51:36 -0000 HI Dave, On Oct 21, 2014, at 00:48 , Dave Taht wrote: > OK, I tried a few combinations of burst and cburst on a cerowrt box, > using 90/10 as a up/download speed. >=20 > burst 64000 cburst 64000 was a bit of a win, in most respects, but odd > in others. >=20 > netperf-wrapper data at: >=20 > http://snapon.lab.bufferbloat.net/~d/burst_tests/ Great, so I see an increase in ingress rate for cburst 64000 = with no real side effects, but burst 64000 cburst 64000 somehow manages = to punish one of the BE streams. Luckily the latency under load increase = stays really small. Do you know whether sirq differed between the tests? = (I assume no it should be pegged to 90-100% during all tests as the = effective good put increased=85) Best Regards Sebastian >=20 >=20 > On Mon, Oct 20, 2014 at 1:04 PM, Dave Taht = wrote: >> On Sun, Oct 19, 2014 at 3:44 PM, Sebastian Moeller = wrote: >>> Hi Dave, >>>=20 >>> so I just went with what I have available, shaping between linux = host on se00 and macbook on sw10, shaper on se00 (25M/25M that is the = maximum wireless throughput with the current router position): = burst/cburst set at 1600(default) 16000 and 16000. And lo and behold the = sirq gets smaller the larger burst/cburst is set. Now tho test is just = too confounded by my bad wireless to be proof, but it certainly = justifies the time to expose knobs in the GUI to set = burst/cburst/quantum values for HTB for each shaper instance independent = for ingress and egress=85 (I do not assume that this will even double = the throughput of a wndr as a router, but even just 10-20% will make a = difference ;) (I will eat my own dogwood, since I am about to upgrade = from 16M/2.5M to 50M/10M right into where our sirq pain starts)). >>=20 >> I don't necessarily think knobs need to be exposed. Perhaps tuning = the >> burst parameter as a function of the >> induced latency would be about right. At 10mbits, a single 1500 byte >> packet takes 1.3ms to egress. So if we >> were to aim for .5-2ms worth of burst across the operational range of >> the shaper, that might work. In the >> case of cable, a grant request takes 2-6ms, anyway. >>=20 >> So at 80mbit, a burst size of 8-16k seems possibly optimal. It could >> be higher (other overheads in the kernel). >>=20 >> Now that we have a knob to jiggle, I'll go jiggle it when I have some = time... >>=20 >> I note that I'm under the impression cburst can be twiddled with also >> to make "powerboost"'s behavior better, >> but I've not seen it work. >>>=20 >>>=20 >>>=20 >>> Best Regards >>> Sebastian >>>=20 >>> On Oct 19, 2014, at 21:27 , Dave Taht wrote: >>>=20 >>>> Yes fiddling with burst seems to make sense. Try 16k >>>>=20 >>>> On Oct 19, 2014 11:56 AM, "Sebastian Moeller" = wrote: >>>> HI Dave, >>>>=20 >>>>=20 >>>> On Oct 19, 2014, at 20:24 , Dave Taht wrote: >>>>=20 >>>>> On at least one verizon device I've tried it appeared that they = had >>>>> SFQ or something similar on egress from the modem. >>>>>=20 >>>>> = http://www.bufferbloat.net/projects/codel/wiki/RRUL_Rogues_Gallery#Verizon= -FIOS-Testing-at-25Mbit-up-and-25Mbit-down >>>>>=20 >>>>> So you only needed to shape the download. which is good as we = start >>>>> peaking out at 50Mbit download total. But only measurements can = tell. >>>>=20 >>>> So on Hnymans community openwrt build a few fortunate ones = on excellent lines seem to get decent results even at 110-120 Mbps = combined: >>>> https://forum.openwrt.org/viewtopic.php?pid=3D250989#p250989 >>>> and: >>>> https://forum.openwrt.org/viewtopic.php?pid=3D251013#p251013 >>>> I have no idea why and both lines were reasonably well-behaved even = without any AQM/QOS... >>>>=20 >>>> Also I wonder whether when we increase the quantum for higher rates = to give HTB some breathing room, whether we also should increase burst = and cburst? My hunch is that quantum affects the switching between the = leaves, while busts and cburst should allow to dump more data to lower = layers inside each leaf qdisc. And since we are running behind, maybe = taking a bigger shovel can help some. (I assume this needs to be = titrated not to kill latency under load, but if we can only effective = have HTB execute x times per second we can easily afford to dump = line-rate/maxHTB_iteratin_rate bytes per opportunity, no?) My own = internet link is way to slow to test this... >>>>=20 >>>> Best Regards >>>> Sebastian >>>>=20 >>>>>=20 >>>>>=20 >>>>> On Sun, Oct 19, 2014 at 10:51 AM, Ernesto Elias = wrote: >>>>>> Hello everyone! >>>>>> I have a question about the wndr3800 routing limit. I went back = to the older >>>>>> submissions to see if I can find what would be the answer for it. = But in my >>>>>> search I haven't managed to find a definite answer. =46rom what I = seen about >>>>>> setting the limit it can do with SQM is 50, 60, or 80 mbit. I'm = just >>>>>> wondering if anyone can shed some light for me here as I have = verizon fios >>>>>> and my speeds are 50 dl/50 ul. Thank you guys very much! >>>>>>=20 >>>>>> _______________________________________________ >>>>>> Cerowrt-devel mailing list >>>>>> Cerowrt-devel@lists.bufferbloat.net >>>>>> https://lists.bufferbloat.net/listinfo/cerowrt-devel >>>>>>=20 >>>>>=20 >>>>>=20 >>>>>=20 >>>>> -- >>>>> Dave T=E4ht >>>>>=20 >>>>> thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks >>>>> _______________________________________________ >>>>> Cerowrt-devel mailing list >>>>> Cerowrt-devel@lists.bufferbloat.net >>>>> https://lists.bufferbloat.net/listinfo/cerowrt-devel >>>>=20 >>>=20 >>=20 >>=20 >>=20 >> -- >> Dave T=E4ht >>=20 >> thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks >=20 >=20 >=20 > --=20 > Dave T=E4ht >=20 > thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks