I'm in the US, but live in a relatively rural area. My only internet options are DSL and satellite. The local provider is Century Link (it used to be Sprint, but they sold their copper phone business off). I have the fastest service that they offer (based on distance from the DSLAM), 4 down / .5 up. I have had SmokePing monitoring my latency to the first hop outside my network for over a year now (I've been on CeroWRT the whole time). My baseline (no load) latency is 31ms. I used to have AQM throttling back to 80% of my already pathetic bandwidth. I would still regularly see periods lasting minutes to hours when latency would be 80 - 120ms. I only recently grokked what you were talking about with tc_stab since I got back from the holidays with the family, I set things up as you suggested for Fred (nfq_codel, "target 25ms" in advanced egress, ATM, per packet overhead 40, and set my SQM bandwidth limits to 95%). Since the 30th my "worst case" latency has been 41ms. Plus I get to use more of my actual bandwidth. I REALLY wish that I'd made the time to read your emails about setting up the ATM overhead earlier. Thank you. -- David P. On Mon, Jan 6, 2014 at 9:27 AM, Sebastian Moeller wrote: > Hi Fred, > > > On Jan 6, 2014, at 15:22 , Fred Stratton wrote: > > > The line rate is 11744/1022 kb/s, but changes moment to moment. SNR is > 12.1 decibel. I am using 11000/950 kb/s as settings. > > So 100 * 11000 / 11744 = 93.66% of downlink line rate and 100* 950 > / 1022 = 92.95 % of uplink line rate; quite impressive given the common > wisdom of 85% :). > > > > I shall try your suggestion when there is something worth watching > live, to provide a valid comparison, which may not be before 21:30 CET on > Sunday. > > Oh, take your time, this is really not essential, butit would be a > nice data point for figuring out how important the correct overhead > estimate really is in real life, theory being theory and all… > > Best Regards > Sebastian > > > > > On 06/01/14 14:12, Sebastian Moeller wrote: > >> Hi Fred, > >> > >> > >> On Jan 6, 2014, at 10:52 , Fred Stratton wrote: > >> > >>> I have been operating the latest build with 6relayd disabled. The > henet /48 I have been allocated is subnetted correctly, presumably by > dnsmasq. > >>> > >>> I adopted the suggestions to use nfq_codel and an egress target of > 25ms , with an overhead of 40 on a PPPoE connection. I chose to watch the > first 2 episodes of the 3 part third series of 'Sherlock', live on iPlayer, > and these streamed correctly and uninterrupted for 90 minutes. This was > not previously possible. (Quite whether they were up to the standard of > previous episodes is another matter.) > >>> > >>> I can watch iPlayer with little stutter whilst downloading Arch Linux > by torrent, downloading other files at the same time. > >>> > >>> So, for a relatively slow ADSL2+ line, the current build works well. > >> Out of curiosity, to what percentage of the "current line rate" > (you know the one reported by your modem) you shaped up- and downlink? And > in case you have too much time on your hand, how does the same feel with an > overhead of 10 (to see how bad an overhead underestimate would feel for a > user), since you currently happen to have a quite sensitive subjective > latency evaluation system set up :)… > >> > >> Best Regards > >> Sebastian > >> > >>> > >>> On 06/01/14 03:29, Dave Taht wrote: > >>>> On Sat, Jan 4, 2014 at 10:40 AM, Fred Stratton > wrote: > >>>>> Link Names: > >>>>> > >>>>> For consistency, if ADSL is used as a portmanteau term, them VDSL > should be > >>>>> used as the equivalent for VDSL and VDSL2. > >>>>> > >>>>> CeroWRT has to decide whether it is an experimental build, or > something that > >>>>> will eventually be used in production, so these decisions can be made > >>>>> consistently. > >>>> Well, what I was aiming for was for us to get the sqm scripts and gui > >>>> up to where they were better than the standard openwrt qos scripts and > >>>> then push them up to openwrt to where they could be more widely > >>>> deployed. > >>>> > >>>> Aside from being able to dynamically assign priorities in the gui, we > >>>> are there. Except that nfq_codel is currently getting better results > >>>> than fq_codel at low bandwidths, and I'm tempted to pour all of > >>>> simple.qos into C. > >>>> > >>>> As for cero's future - certainly since all the snowden revelations > >>>> I've been going around saying that "friends don't let friends run > >>>> factory firmware". I would like a stable build of sqm and cerowrt to > >>>> emerge, and to then go off and work on improving wifi. Regrettably > >>>> what seems to be happening is more backwards than forwards on the > >>>> former, and ramping up on the ath9k and ath10k is taking more time > >>>> than I'd like, and it seems likely I'll be working on those primarily > >>>> on another platform and only eventually pushing the results out to > >>>> cero, mainline kernel > >>>> > >>>> So it's still at the "keep plugging away" point for sqm, ipv6, cero in > >>>> general, with the stable release always just out of sight. > >>>> > >>>> Tackling the ipv6 problem is next on my agenda on cero, and getting a > >>>> test suite going is next on my day job. > >>>> > >>>>> I concur with your ADSL setup suggestion as default. I have been > running the > >>>>> Sebastian Moeller ping script overnight to calculate ADSL overhead > for the > >>>>> last several days. After several hours of curve fitting using > Octave, an > >>>>> overhead result is displayed. This novel approach works well. > >>>> It would be nice to get to where we could autoconfigure a router using > >>>> tools like these with no human intervention. This includes bandwidth > >>>> estimation. > >>>> > >>>>> The overhead for the particular setup I use was 40 for PPPoE, and 10 > for > >>>>> PPPoA. > >>>>> > >>>>> The default you suggest is a suitable starting point, I suggest. > >>>>> > >>>>> > >>>>> On 04/01/14 18:16, Rich Brown wrote: > >>>>>> QUESTION #5: I still don’t have any great answers for the Link Layer > >>>>>> Adaptation overhead descriptions and recommendations. In an earlier > message, > >>>>>> (see > >>>>>> > https://lists.bufferbloat.net/pipermail/cerowrt-devel/2013-December/001914.html > >>>>>> and following messages), Fred Stratton described the overheads > carried by > >>>>>> various options, and Sebastian Moeller also gave some useful advice. > >>>>>> > >>>>>> After looking at the options, I despair of giving people a clear > >>>>>> recommendation that would be optimal for their equipment. > Consequently, I > >>>>>> believe the best we can do is come up with “good enough” > recommendations > >>>>>> that are not wrong, and still give decent performance. > >>>>>> > >>>>>> In this spirit, I have changed Draft #3 of the “Setting up SQM” > page to > >>>>>> reflect this understanding. See > >>>>>> > http://www.bufferbloat.net/projects/cerowrt/wiki/Setting_up_AQM_for_CeroWrt_310 > >>>>>> > >>>>>> ADSL/ATM link: Choose “ADSL/ATM", and set Per Packet > Overhead to > >>>>>> 40 > >>>>>> VDSL2 link: Choose “VDSL”, and set Per Packet Overhead to 8 > >>>>>> Other kind of link (e.g., Cable, Fiber, Ethernet, other not > >>>>>> listed): Choose “None (default)”, and set Per Packet Overhead to 0 > >>>>>> > >>>>>> NB: I have changed the first menu choice to “ADSL/ATM” and the > second to > >>>>>> “VDSL” in the description. I would ask that we change to GUI to > reflect > >>>>>> those names as well. This makes it far easier/less confusing to > talk about > >>>>>> the options. > >>>>>> > >>>>>> As always, I welcome help in setting out clear recommendations that > work > >>>>>> well for the vast majority of people who try CeroWrt. Thanks. > >>>>>> > >>>>>> Rich > >>>>>> _______________________________________________ > >>>>>> Cerowrt-devel mailing list > >>>>>> Cerowrt-devel@lists.bufferbloat.net > >>>>>> https://lists.bufferbloat.net/listinfo/cerowrt-devel > >>>>> _______________________________________________ > >>>>> Cerowrt-devel mailing list > >>>>> Cerowrt-devel@lists.bufferbloat.net > >>>>> https://lists.bufferbloat.net/listinfo/cerowrt-devel > >>>> > >>> _______________________________________________ > >>> Cerowrt-devel mailing list > >>> Cerowrt-devel@lists.bufferbloat.net > >>> https://lists.bufferbloat.net/listinfo/cerowrt-devel > > > > _______________________________________________ > Cerowrt-devel mailing list > Cerowrt-devel@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cerowrt-devel >