Hi Dennis,? On June 10, 2016 4:05:11 PM GMT+02:00, Dennis Fedtke <dennisfed...@gmail.com> wrote: >Hi Sebastian, > >yes this is wired connection. As i stated my ping times always vary >independently of target. >My ISP is overloaded in certain regions. So i assume they do some >shaping/limiting on certain protocols (icmp for example) >Connection speed is 200/20 Mbit.
Okay that is a Docsis cable Link, so no atm encapsulation at all. There a several lines of reasoning to one to this conclusion, but mainly ATM links top out at 22Mbps, and in Germany typically at 16-17Mbps, and your ISP is a pure cable. Company. So you can stop running the overhead detector as that only works on ATM links, sorry. I have not yet found a way to measure the overhead without ATM cells. >ISP is unitymedia which doesn't allow you to use your own hardware. The law changed an soon, August I believe they will have to give you the access information, but you will still need a cable modem or Docsis router... >So actually i have to run my router behind theirs with exposed host >enabled :< > >Ping response: > >ping -s 1400 -c 1 109.90.x.x >PING 109.90.28.1 (109.90.28.1) 1400(1428) bytes of data. >1408 bytes from 109.90.28.1: icmp_seq=1 ttl=253 time=11.6 ms > >--- 109.90.28.1 ping statistics --- >1 packets transmitted, 1 received, 0% packet loss, time 0ms >rtt min/avg/max/mdev = 11.677/11.677/11.677/0.000 ms > >This looks good or? Yes the ping is fine, I assume that your node is quite overbooked and you the 4ms variance from the Docsis grant request system or so. But I am no Docsis expert, so that could be wrong... > >Yes i am from germany. So you are from germany too? Yes. > >Thanks for your time and help :) Happy to be able to help.... > > >Best regards >Dennis Freundlichem Gruessen Sebastian > >Am 10.06.2016 um 15:02 schrieb moeller0: >> Hi Dennis, >> >>> On Jun 10, 2016, at 14:43 , Dennis Fedtke <dennisfed...@gmail.com> >wrote: >>> >>> Hi Sebastian, >>> >>> i used the default setting of 1000. >> Okay, that should work i assume unless you have a very fast link… >What link at what ISP do you actually have? >> >>> But it seems that my isp is dropping icmp packets if there are >exceeding some sending threshold. >> I would be amazed if they did, a sympotom of that would be rsate >reduction to all ICMP probe flows independent of target host. If >however you only see this with specific hosts it is very likely that >that host rate limits its ICMP responses. In either case try another >host further upstream. II think I has reasonable decent results with >targeting 8.8.8.8, googles dns servers. >> >>> So there is a lot of none usable ping data. >> Again, try another host… >> >>> I increased the send delay to 50ms. 25 ms already shows dropped >requests. >> That might also help, as long as you stay below their throttling >rate the chosen host might still work okay. >> >>> This is the third run now. Waiting for completion. >> Well, sorry that the method is not as slick and streamlined, but >there are no guarded good ICMP reflectors available on the net. >> >>> The ping target is my first hop. >> Try the next hop then ;) >> >>> Actually my ping always varies around +-5ms even at idle and >independently of ping target. >> This is via wifi/wlan? If so try from a wired connection instead. >> >>> When i look through the ping file the increase in ping times are >actually appear to be random to me. >> Well, we expect variability of the individual “trials” to exist, >that is why we collect so many and try to select the best measure in >the matlab code to remove the unwanted variance. Could you post a link >to both of the generated plots please, the first one showing te >different aggregation measures might be helpful in diagnosing the >issues deeper. >> >>> So how to test if my isp responses with fixed icmp packet size? >> You could try manually. In the folloewing example I pinged >gstatic.com (which belongs to googles CDN as far as I know): >> >> bash-3.2$ ping -s 1 -c 1 gstatic.com >> PING gstatic.com (216.58.213.195): 1 data bytes >> 9 bytes from 216.58.213.195: icmp_seq=0 ttl=55 >> >> --- gstatic.com ping statistics --- >> 1 packets transmitted, 1 packets received, 0.0% packet loss >> >> >> bash-3.2$ ping -s 64 -c 1 gstatic.com >> PING gstatic.com (216.58.213.195): 64 data bytes >> 72 bytes from 216.58.213.195: icmp_seq=0 ttl=55 time=19.446 ms >> >> --- gstatic.com ping statistics --- >> 1 packets transmitted, 1 packets received, 0.0% packet loss >> round-trip min/avg/max/stddev = 19.446/19.446/19.446/0.000 ms >> >> >> bash-3.2$ ping -s 65 -c 1 gstatic.com >> PING gstatic.com (216.58.213.195): 65 data bytes >> 72 bytes from 216.58.213.195: icmp_seq=0 ttl=55 time=21.138 ms >> wrong total length 92 instead of 93 >> >> --- gstatic.com ping statistics --- >> 1 packets transmitted, 1 packets received, 0.0% packet loss >> round-trip min/avg/max/stddev = 21.138/21.138/21.138/0.000 ms >> bash-3.2$ >> >> >> bash-3.2$ ping -s 1400 -c 1 gstatic.com >> PING gstatic.com (216.58.213.195): 1400 data bytes >> 72 bytes from 216.58.213.195: icmp_seq=0 ttl=55 time=6.878 ms >> wrong total length 92 instead of 1428 >> >> --- gstatic.com ping statistics --- >> 1 packets transmitted, 1 packets received, 0.0% packet loss >> round-trip min/avg/max/stddev = 6.878/6.878/6.878/0.000 ms >> >> Once I try to send 65 Bytes of ICMP payload the response is cut short >to 92 bytes, the same might happen with your isp. But also if all your >ISP does is rate limiting the ICMP packests that still can lead to to >much variance in the RTTs… >> >> >>> Im in central europe too :D >> Ah, then you just have a different work/sleep cycle than I do ;). >Where in central Europe, if I might as Ii am, as you might have guessed >based in Germany… >> >> Best Regards >> Sebastian >> >>> Thanks :) >>> >>> >>> Am 10.06.2016 um 07:20 schrieb moeller0: >>>> Hi Dennis, >>>> >>>> >>>>> On Jun 10, 2016, at 02:49 , Dennis Fedtke <dennisfed...@gmail.com> >wrote: >>>>> >>>>> Hi Sebastian, >>>>> >>>>> Sorry this is positive or? >>>> I would say that is unclear… >>>> >>>>> But i need more samples ? >>>> I would try with more samples, after checking that the ping times >in the recorded data file actually are larger for larger probes than >for smaller, some hosts will reply with a fixed maximum ICMP packet >instead of returning the received packet, thereby reducing the signal >range (as only the upload leg of the link is meaning fully contributing >useful differential signal. >>>> BTW I am in central europe so at times of the day my responses can >be very sporadic, as I either am at work or sleeping ;) >>>> >>>> Best Regards >>>> Sebastian >>>> >>>>> Thanks :) >>>>> >>>>> >>>>> Am 10.06.2016 um 01:11 schrieb moeller0: >>>>>> Hi Dennis, >>>>>> >>>>>>> On Jun 10, 2016, at 00:45 , Dennis Fedtke ><dennisfed...@gmail.com> wrote: >>>>>>> >>>>>>> Hi Sebastian, >>>>>>> >>>>>>> thank you for your answers :) >>>>>>> >>>>>>> The ATM overhead detector script is currently running. >>>>>>> I read the wiki about it but im not quite sure how to interpret >the plot. >>>>>>> I mean what info should i read from it? maximum packet size? >>>>>> The relevant number is reported as “Estimated overhead preceding >the IP header” in the top part of the second figure created by the >script. But that is only relevant.useful if you see a nice step like >plot in figure 2 as well ( the second figure in >https://github.com/moeller0/ATM_overhead_detector/wiki as positive and >the fourth figure as negative example. >>>>>> >>>>>>> If yes do i set the overhead in cake? Or do i set iptables to >clamp to new mtu/mss? >>>>>> If you use plain cake and you know the numerical overhead (NN) >the easiest is to add the following to your cake invocation: “atm >overhead NN” >>>>>> >>>>>> Please note that if you use cake on an ethernet interface the >kernel will already account for 14 byte of ethernet overhead, so if the >script told you 44 as actual overhead, you use ”overhead 30” to address >that. If you use a pppoe interface the kernel will most likely not add >the 14 bytes for you, so then you would use “overhead 44” (I excluded >the atm option in the last examples for clarity…) >>>>>> >>>>>>> Regarding UDP paket dropping problem: >>>>>>> I just read some forums and users stated that under heavy load >cake starts to drop udp packets which causes lag ingame. >>>>>>> My idea was to set ingress/egress to diffserv4 and apply the EF >dscp mark on those packets. >>>>>> Ell, not a bad idea, but often the problem are in the incoming >traffic, and unfortunately with the ifb we use we can not use iptables, >but only tc, and remarking with tc is unpleasant. >>>>>> >>>>>>> Will this even work? if yes how to do this? iptables? >>>>>> No, you wuld need tp use tc. >>>>>> >>>>>>> ipt -t mangle -A PREROUTING -p udp -m multiport --ports >5000:5500 -j DSCP --set-dscp-class EF >>>>>>> >>>>>>> Like thia? Is prerouting correct here? (Taken from layer cake >script) >>>>>> This will affect outgoing packets and might be a good idea in >your specific case. >>>>>> >>>>>> BUT why don’t you try the default behaviour with specific rules >and tricks and report success or failure back to us, after all the >fastest/easiest classification is one one does not need to perform at >all. >>>>>> >>>>>>> For the squash and wash feature. >>>>>>> Im asking because if i choose to squash in the advanced options >of sqm scripts. >>>>>>> The dscp fields/marks will be overwritten by iptables to 0 >(besteffort). (layer cake script) >>>>>>> So then it makes no sense to manually set dscp fields/marks or? >(Or even setting diffserv) >>>>>> No unfortunately on ingress cake sees the packets before >iptables, so the effective behavioral emulation of wash/squash by cake >is to set ingress cake to besteffort (basically cake ignores the dscp >field which functionally is identical to all packets having the same >value). The squashing by iptables just clears the dscp marls so that >internal networking elements like potentially wifi liknks are not >confuzed by the dscp information. >>>>>> >>>>>>> Did i understand this correctly. Per rfc isps should not provide >dscp fields/marks? >>>>>> Not exactly, per RFC DSCPs are only ever valid/defined inside a >DSCP domain and your ISPs domain ends before it reaches your CPE. Since >you have no control over your ISPs markings, they can be very much not >like you want them to be (Dave That reported that his ISP re-mapped >almost 1/3 or so of packets into the CS1 background class). So it is >recomended that each DSCP domain re-mapps the code points at its entry >point, which in your case is your router… >>>>>> >>>>>> Best Regards >>>>>> Sebastian >>>>>> >>>>>>> Thank you. >>>>>>> >>>>>>> >>>>>>> >>>>>>> Am 09.06.2016 um 23:30 schrieb moeller0: >>>>>>>> Hi Dennis, >>>>>>>> >>>>>>>> let me start with a disclaimer, I am not the best information >source for cake on this mailing list, but I assume the others will >chime in if I say something questionable… >>>>>>>> >>>>>>>>> On Jun 9, 2016, at 22:58 , Dennis Fedtke ><dennisfed...@gmail.com> wrote: >>>>>>>>> >>>>>>>>> Hi >>>>>>>>> >>>>>>>>> Currently im running lede + cake + sqm_scripts and i have some >questions: >>>>>>>>> >>>>>>>>> 1. What is considered the “optimal" setup atm for cake? >>>>>>>> The same as without cake; really, proper per-packet-overhead >accounting is important for bandwidth shaping, especially for ATM >-based links. I would recommend to follow the method on >https://github.com/moeller0/ATM_overhead_detector to m\empirically >measure whether your link uses ATM encapsulation and what exact >overhead is in use. >>>>>>>> >>>>>>>>> e.g. which cake script should i use piece or layer cake? >>>>>>>> piece_of_cake has only one tier of priority, while layer_cake >currently offers 4. Packets are put into the different priority bands >based on the content of their TOS/DSCP filed in the IP header; if this >is greek to you, I guess piece_of_cake most likely is what you are >looking for.. >>>>>>>> >>>>>>>>> 2. Recently squash and wash was removed. >>>>>>>>> But the sqm scripts were not updated. In the advanced options >should i set that the dcsp marks are kept? >>>>>>>> This really is an implementation detail that has no immediate >effect if you choose piece_of_cake as typically only the bottleneck is >sensitive to DSCP based priority banding. (Typically in that if you are >unlucky your WLAN will use the DSCP marks to move packets into 4 >different priority classes, which is fine if you want that, but bad for >not sanity checked packets coming in from the wider internet (one is >not supposed to assume incoming packets have sensible dscp markings as >per RFC) that is why the wash/squash option is missed by some of us, >independent of the fact that it was a layering violation). >>>>>>>> >>>>>>>>> 3. Should i use advanced options in sqm scripts and set >triple-isolate + diffserv8 ? >>>>>>>> If you understand what these options do and believe that this >is the best for your network go ahead, otherwise… The triple-isolate >option will try to be fair to host_IP addresses first and then for each >hostIP fair to each flow, but for that to do something you will most >likely want this requires that cake sees internal IP addresses of your >end-hosts. In the typical configuration with SQM on the WAN interface >of a NAT router all internal addresses are replaced with the external >IP address of the router it self and triple-isolates per host fairness >will pretty much be equal to per flow fairness (not exactly, but in >essence). So if you want to try tiple-isolate or its better defined >brothers dual-srchost and dual-dsthost you would need to instantiate >SQM on an internal interface like LAN. But then the direction of >ingress and egress from the routers perspective changes with regards to >the internet download and upload direction and you will need to put the >internet upload bandwidth into the download field of the sqm GUI and >vice versa. Also SQM on an internal interface will also shape internal >traffic over the same interface, and that often affects traffic to and >from the wifi/wlan radios to the lan switch… (I guess you would have >preferred a shorter less vague response, but such are the constraints…) >>>>>>>> >>>>>>>>> 4. Is it recommend to enable diffserv on ingress? >>>>>>>> If you trust/konw/have confirmed that your upstream (ISP?) >sends you sensible and reasonable DSCP markings by all means enable >diffserv on ingress. But the default assumption should be that your >upstream used a dscp mapping that only makes sense for them and not for >you. >>>>>>>> >>>>>>>>> 5. Is there still the udp packet dropping problem? e.g. games >that are using udp. >>>>>>>>> If yes does it make sense to apply diffserv classes manually? >How to do this? >>>>>>>> I am not sure what you mean, but if you test this and have >some findings please report here… >>>>>>>> >>>>>>>>> 6. is the autorate_ingress still under development? >>>>>>>>> This very interesting feature. especially for docsis networks. >Will it be possible to set target ping time? >>>>>>>> The last tests did indicate that this feature is not ready for >primetime at least not on typically fixed bandwidth links and I assume >docsis links are fixed enough. >>>>>>>> >>>>>>>>> 6. What difference does it make to set a different rtt? >>>>>>>>> Setting lower rtt will reduce download speed i guess but will >it allow better ping times (because of lower downloadrate uh)? >>>>>>>>> What happens if rtt is set way higher? >>>>>>>> With the RTT parameter you in essence specify how much time >you give the endpoints of a flow to respond to a congestion signal (ECN >marking or packet drop) if you select this way to small you will >sacrifice bandwidth, if you set this too high you will accumulate more >latency under load. The good thing seems to be that this does not need >to be terribly precise, order of magnitude correctness seems to be >sufficient (at least in base2) >>>>>>>> >>>>>>>> >>>>>>>>> Thank you! >>>>>>>> I am sure the real experts will also chime in… >>>>>>>> >>>>>>>> Best Regards >>>>>>>> Sebastian >>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Cake mailing list >>>>>>>>> Cake@lists.bufferbloat.net >>>>>>>>> https://lists.bufferbloat.net/listinfo/cake >>>>>>> _______________________________________________ >>>>>>> Cake mailing list >>>>>>> Cake@lists.bufferbloat.net >>>>>>> https://lists.bufferbloat.net/listinfo/cake >>> -- Sent from my Android device with K-9 Mail. Please excuse my brevity. _______________________________________________ Cake mailing list Cake@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/cake