Regarding picking up advanced congestion management in a result, it would be possible by adding a concurrent tcpdump on each test server - running all the time and filtering for the appropriate bits.
But am I just looking for "ECN capable" flags originating from a given public IP? or am I filtering just for CE marks (11), indicating there was some active queue management actually going on -- and only that would be worth mentioning? thanks On Thu, Apr 7, 2016 at 1:30 AM, Dave Taht <[email protected]> wrote: > On Tue, Apr 5, 2016 at 8:19 PM, jb <[email protected]> wrote: >> I take your point regarding Quality > > Thx! I am not grumpy at you in particular, but at a world that > continues to view packet loss as completely undesirable (I was at > several ietf meetings like that yesterday, and 2 days ago the > FCC's "nutrition labels for broadband" got a lot of press: > http://arstechnica.com/business/2016/04/fccs-nutrition-labels-for-broadband-show-speed-caps-and-hidden-fees/ > ) > > Does anyone know how these nutrition labels are calculated? > >> but both your examples in the post show A+ quality? > > Well, yes... :) I did both of those with ecn on. (I did also get an A+ > with ecn off) > > "desirable" packet loss, varies based on the number of flows, the > targetted queuing delay, the bandwidth of the link, the tcp, and the > RTT. It rapidly drops into the low percentage points for this > particular test,for those particular parameters. > > as for: > > "Quality Grades > > Quality refers to average detected packet loss / re-transmit > percentages during download phase. The higher the packet loss / > re-transmit percentage the more inefficient the connection is, and a > very poor result may be indicative of congestion, inside wiring issues > or other problems that need addressing. > > "1% or less - A+ > 2.5% or less - A > 3% or less - B > 5% or less - C > 12% or less - D > over 12% - F" > > What I specifically objected to was this formula for calculating the > grade. After stewing about it a while (um, er, *years*, now), I > realized last night that with a little work, now that we know what > aqms such as pie and fq_codel can achieve, that we could, indeed, get > a desirable range of "packet loss" for X flows, Y RTT, and Z > bandwidth. > > btw: Does your test have the ability to track "CE" marks? That would > be like a "gold star" affixed to the test report. (latest IoS has some > support for ecn now by default) > >> I'm thinking that packet loss significant enough to show as a "C" or >> worse is mostly a bad situation > > I pointed at a case where 25% packet loss was good here. > > http://localhost:1313/post/rtt_fair_on_wifi/ > > I am tempted to build on this theme, because it is not intuitive that > desirable loss is a curve - a lot at low rates, but at higher rates, > much less loss occurs and and really high rates one loss hurts... > >> even if avoiding all packet loss - by using huge buffers - is >> definitely a disaster.. > > Yes. 0 and major bufferbloat would be an F grade for me, for "Quality" :) > > In other news, I sure wish the cable modems out there had followed > these guidelines at least. > > http://www.cablelabs.com/wp-content/uploads/specdocs/CM-GL-Buffer-V01-110915.pdf > >> >> >> On Wed, Apr 6, 2016 at 12:21 PM, Dave Taht <[email protected]> wrote: >>> On Tue, Apr 5, 2016 at 6:33 PM, Brandon Applegate <[email protected]> wrote: >>>> >>>>> On Apr 5, 2016, at 9:04 PM, Dave Taht <[email protected]> wrote: >>>>> >>>>> Does anyone know what the "quality" portion of dslreport's metric means? >>>> >>>> Basically - packet loss. >>>> >>>> https://www.dslreports.com/faq/17930 >>> >>> Sigh. I ranted. I might rant harder. >>> >>> http://blog.cerowrt.org/post/bufferbloat_vs_quality/ >>> >>>> >>>> — >>>> Quality Grades >>>> >>>> Quality refers to average detected packet loss / re-transmit percentages >>>> during download phase. The higher the packet loss / re-transmit percentage >>>> the more inefficient the connection is, and a very poor result may be >>>> indicative of congestion, inside wiring issues or other problems that need >>>> addressing. >>>> >>>> 1% or less - A+ >>>> 2.5% or less - A >>>> 3% or less - B >>>> 5% or less - C >>>> 12% or less - D >>>> over 12% - F >>>> — >>>> >>>> >>>> _______________________________________________ >>>> Bloat mailing list >>>> [email protected] >>>> https://lists.bufferbloat.net/listinfo/bloat >>>> >>> _______________________________________________ >>> Bloat mailing list >>> [email protected] >>> https://lists.bufferbloat.net/listinfo/bloat _______________________________________________ Bloat mailing list [email protected] https://lists.bufferbloat.net/listinfo/bloat
