From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-x229.google.com (mail-oi0-x229.google.com [IPv6:2607:f8b0:4003:c06::229]) (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 9637E21F2CF for ; Mon, 20 Oct 2014 15:48:04 -0700 (PDT) Received: by mail-oi0-f41.google.com with SMTP id u20so17452oif.14 for ; Mon, 20 Oct 2014 15:48:03 -0700 (PDT) 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=8/NlvXz6YE6F+TElMNDXqEAps/MJVExdDUPQYe1HbFk=; b=haZ7YdyzYzZYRL0VqarHNqtMujbTZ3kLbwfAqenrIicCiEVdjHgltjVOqt8SWDmyuH 7tRd71BKvWsH0G0RiZQwJVNpm6EEEYfNx/GAbnki7edkBbYm7XiUOvr11ZSWdCcEGvbg 0nH2jb8b8h8QBu4gE50XBvIGbf7vOQAG+veQXEXz+kba6sZ/AOFfAkGegRuK5ALxF74k gvSNJg44LRnyNGWKRVAIzTb5K2+PziKvtE6FmHaAPKP/kU0t4dcMWPI4DmXQ2SAHLSlu LNT2/Q1GvZEusJfak3BNA/lkHw+zV1nXiZCeOhuIxbv17WA0vIzU0pydrLJnM32zZOjF V2/A== MIME-Version: 1.0 X-Received: by 10.202.51.132 with SMTP id z126mr4641894oiz.57.1413845282961; Mon, 20 Oct 2014 15:48:02 -0700 (PDT) Received: by 10.202.227.211 with HTTP; Mon, 20 Oct 2014 15:48:02 -0700 (PDT) In-Reply-To: References: <7B5DD5A3-D273-4708-909C-5B5D5DE72282@gmx.de> <440DFB9A-C4F8-4723-A407-20ABDBB7BD09@gmx.de> Date: Mon, 20 Oct 2014 15:48:02 -0700 Message-ID: From: Dave Taht To: Sebastian Moeller Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable 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: Mon, 20 Oct 2014 22:48:32 -0000 OK, I tried a few combinations of burst and cburst on a cerowrt box, using 90/10 as a up/download speed. burst 64000 cburst 64000 was a bit of a win, in most respects, but odd in others. netperf-wrapper data at: http://snapon.lab.bufferbloat.net/~d/burst_tests/ On Mon, Oct 20, 2014 at 1:04 PM, Dave Taht wrote: > On Sun, Oct 19, 2014 at 3:44 PM, Sebastian Moeller wrot= e: >> Hi Dave, >> >> 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 wire= less throughput with the current router position): burst/cburst set at 1600= (default) 16000 and 16000. And lo and behold the sirq gets smaller the larg= er burst/cburst is set. Now tho test is just too confounded by my bad wirel= ess 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 in= dependent for ingress and egress=E2=80=A6 (I do not assume that this will e= ven 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 upgrad= e from 16M/2.5M to 50M/10M right into where our sirq pain starts)). > > 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. > > So at 80mbit, a burst size of 8-16k seems possibly optimal. It could > be higher (other overheads in the kernel). > > Now that we have a knob to jiggle, I'll go jiggle it when I have some tim= e... > > 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. >> >> >> >> Best Regards >> Sebastian >> >> On Oct 19, 2014, at 21:27 , Dave Taht wrote: >> >>> Yes fiddling with burst seems to make sense. Try 16k >>> >>> On Oct 19, 2014 11:56 AM, "Sebastian Moeller" wrote: >>> HI Dave, >>> >>> >>> On Oct 19, 2014, at 20:24 , Dave Taht wrote: >>> >>> > On at least one verizon device I've tried it appeared that they had >>> > SFQ or something similar on egress from the modem. >>> > >>> > http://www.bufferbloat.net/projects/codel/wiki/RRUL_Rogues_Gallery#Ve= rizon-FIOS-Testing-at-25Mbit-up-and-25Mbit-down >>> > >>> > 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. >>> >>> So on Hnymans community openwrt build a few fortunate ones on e= xcellent 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 wit= hout any AQM/QOS... >>> >>> 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 cbu= rst? My hunch is that quantum affects the switching between the leaves, whi= le busts and cburst should allow to dump more data to lower layers inside e= ach leaf qdisc. And since we are running behind, maybe taking a bigger shov= el can help some. (I assume this needs to be titrated not to kill latency u= nder 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 oppo= rtunity, no?) My own internet link is way to slow to test this... >>> >>> Best Regards >>> Sebastian >>> >>> > >>> > >>> > 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 t= he older >>> >> submissions to see if I can find what would be the answer for it. Bu= t in my >>> >> search I haven't managed to find a definite answer. From 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 verizo= n fios >>> >> and my speeds are 50 dl/50 ul. Thank you guys very much! >>> >> >>> >> _______________________________________________ >>> >> Cerowrt-devel mailing list >>> >> Cerowrt-devel@lists.bufferbloat.net >>> >> https://lists.bufferbloat.net/listinfo/cerowrt-devel >>> >> >>> > >>> > >>> > >>> > -- >>> > Dave T=C3=A4ht >>> > >>> > 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 >>> >> > > > > -- > Dave T=C3=A4ht > > thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks --=20 Dave T=C3=A4ht thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks