So here are results from the same Nokia 6.2 Android11 device, once over LTE (with the ISP's shaper set to apparently 25/10) and once over WiFI (5GHz) where the actual limit comes from SQM set to 105/36 (on a VDSL2-link with 116/37 sync). Both results are less than perfect, but over LTE the bloat is quite painful (due to the lack of a time resolved display it is hard to estimate how much of the High result is just happening during the initial peak of the transfer, where it seems that the shaper kicks in with a delay, or potentially it might just allow bursts). Looking at the time resolved results for LTE on DSL reports (http://www.dslreports.com/speedtest/71047363) seems to indicate that it is not only the initial peak: Download (LTE): Download (WiFi): Upload (LTE): Upload (WiFi): (I clearly have some issues with repeated upload delay up to 600-800ms in this test). A flent test over ethernet however shows RTT maxima (of seprate RTT measurement flows so not intra-dataflow RTTs, max tcp_rtt stays below 50ms for all data flows, but that is already smoothed data IIRC): Ping (ms)::ICMP : 28.54 28.40 36.00 ms 1397 Ping (ms)::UDP 0 (CS0) : 28.50 28.33 35.21 ms 1628 Ping (ms)::UDP 1 (CS1) : 28.11 28.22 34.73 ms 1628 Ping (ms)::UDP 2 (CS2) : 26.49 26.26 34.93 ms 1628 Ping (ms)::UDP 3 (CS3) : 26.46 26.32 34.05 ms 1628 Ping (ms)::UDP 4 (CS4) : 26.40 26.21 34.65 ms 1628 Ping (ms)::UDP 5 (CS5) : 26.47 26.28 35.08 ms 1628 Ping (ms)::UDP 6 (CS6) : 29.32 29.26 37.26 ms 1628 Ping (ms)::UDP 7 (CS7) : 28.90 28.81 35.97 ms 1628 TCP download avg : 11.90 N/A N/A Mbits/s 1628 TCP download sum : 95.22 N/A N/A Mbits/s 1628 TCP download::0 (CS0) : 11.95 12.30 15.07 Mbits/s 1628 TCP download::1 (CS1) : 11.72 12.23 13.94 Mbits/s 1628 TCP download::2 (CS2) : 11.92 12.31 14.31 Mbits/s 1628 TCP download::3 (CS3) : 11.84 12.29 14.00 Mbits/s 1628 TCP download::4 (CS4) : 11.83 12.30 14.12 Mbits/s 1628 TCP download::5 (CS5) : 12.05 12.31 15.01 Mbits/s 1628 TCP download::6 (CS6) : 11.93 12.30 14.96 Mbits/s 1628 TCP download::7 (CS7) : 11.98 12.32 14.47 Mbits/s 1628 TCP totals : 125.83 N/A N/A Mbits/s 1628 TCP upload avg : 3.83 N/A N/A Mbits/s 1628 TCP upload sum : 30.61 N/A N/A Mbits/s 1628 TCP upload::0 (CS0) : 4.27 4.31 7.17 Mbits/s 1628 TCP upload::0 (CS0)::tcp_cwnd : 13.37 13.00 20.00 955 TCP upload::0 (CS0)::tcp_delivery_rate : 4.12 4.23 5.57 955 TCP upload::0 (CS0)::tcp_pacing_rate : 5.31 5.45 7.65 955 TCP upload::0 (CS0)::tcp_rtt : 35.24 34.45 48.87 955 TCP upload::0 (CS0)::tcp_rtt_var : 2.36 1.98 11.09 955 TCP upload::1 (CS1) : 1.74 1.76 2.70 Mbits/s 1628 TCP upload::1 (CS1)::tcp_cwnd : 8.18 8.00 13.00 951 TCP upload::1 (CS1)::tcp_delivery_rate : 1.65 1.72 2.95 951 TCP upload::1 (CS1)::tcp_pacing_rate : 2.21 2.29 4.39 951 TCP upload::1 (CS1)::tcp_rtt : 52.63 51.92 73.08 949 TCP upload::1 (CS1)::tcp_rtt_var : 6.30 6.00 16.16 949 TCP upload::2 (CS2) : 4.24 4.31 5.30 Mbits/s 1628 TCP upload::2 (CS2)::tcp_cwnd : 13.10 13.00 18.00 948 TCP upload::2 (CS2)::tcp_delivery_rate : 4.11 4.22 5.19 947 TCP upload::2 (CS2)::tcp_pacing_rate : 5.25 5.42 7.13 948 TCP upload::2 (CS2)::tcp_rtt : 34.81 34.56 46.65 946 TCP upload::2 (CS2)::tcp_rtt_var : 2.43 2.11 10.81 946 TCP upload::3 (CS3) : 4.27 4.38 5.19 Mbits/s 1628 TCP upload::3 (CS3)::tcp_cwnd : 13.29 13.00 18.00 949 TCP upload::3 (CS3)::tcp_delivery_rate : 4.13 4.25 5.08 948 TCP upload::3 (CS3)::tcp_pacing_rate : 5.30 5.52 6.82 949 TCP upload::3 (CS3)::tcp_rtt : 34.99 34.73 45.70 947 TCP upload::3 (CS3)::tcp_rtt_var : 2.39 2.03 11.09 947 TCP upload::4 (CS4) : 4.26 4.37 5.23 Mbits/s 1628 TCP upload::4 (CS4)::tcp_cwnd : 13.33 13.00 18.00 950 TCP upload::4 (CS4)::tcp_delivery_rate : 4.10 4.23 5.05 949 TCP upload::4 (CS4)::tcp_pacing_rate : 5.27 5.47 6.79 950 TCP upload::4 (CS4)::tcp_rtt : 35.29 34.94 46.76 947 TCP upload::4 (CS4)::tcp_rtt_var : 2.43 2.11 11.32 947 TCP upload::5 (CS5) : 4.25 4.32 5.51 Mbits/s 1628 TCP upload::5 (CS5)::tcp_cwnd : 14.06 14.00 19.00 948 TCP upload::5 (CS5)::tcp_delivery_rate : 4.10 4.24 5.24 947 TCP upload::5 (CS5)::tcp_pacing_rate : 5.23 5.42 6.94 948 TCP upload::5 (CS5)::tcp_rtt : 37.51 36.82 47.57 943 TCP upload::5 (CS5)::tcp_rtt_var : 2.27 1.96 9.95 943 TCP upload::6 (CS6) : 3.81 3.87 5.01 Mbits/s 1628 TCP upload::6 (CS6)::tcp_cwnd : 12.08 12.00 17.52 949 TCP upload::6 (CS6)::tcp_delivery_rate : 3.68 3.80 4.96 948 TCP upload::6 (CS6)::tcp_pacing_rate : 4.70 4.88 6.50 949 TCP upload::6 (CS6)::tcp_rtt : 35.90 35.32 48.65 946 TCP upload::6 (CS6)::tcp_rtt_var : 2.67 2.33 9.81 946 TCP upload::7 (CS7) : 3.77 3.85 4.85 Mbits/s 1628 TCP upload::7 (CS7)::tcp_cwnd : 11.91 12.00 17.00 950 TCP upload::7 (CS7)::tcp_delivery_rate : 3.62 3.77 4.83 949 TCP upload::7 (CS7)::tcp_pacing_rate : 4.63 4.83 6.34 949 TCP upload::7 (CS7)::tcp_rtt : 35.91 35.15 47.73 947 TCP upload::7 (CS7)::tcp_rtt_var : 2.56 2.31 9.04 947 cpu_stats_root@192.168.42.1::load : 0.37 0.35 0.83 1214 Now, this clearly is not apples to apples, since flent does not run on my phone and this test was over ethernet, but I think it demonstrates that the upload latency spikes over WiFi are not my ISP's responsibility, but something in my WiFi set-up that needs fixing. I am living next door to a CO and "my" LTE antenna is around 20-30m away (distance phone to antenna element). Might I propose to add time resolved latency plots to the two time resolved speed lines in the detailed results view, please? Regards Sebastian