So I'm at a loss (pun intended). I'm seeing packet loss but only on the return leg (showing in iperf but not WinMTR or ping), and only in Windows 11. If I boot up into Ubuntu 22.04, I get minimal loss (acceptable levels). This is heavily impacting download speeds on international routes. I have a 400Mbps fibre line, and getting download speeds of 20 - 50Mbps internationally due to the packet loss.
Below is a summary of what I've tried and found:
- I'm using the latest drivers for the motherboard (Gigabyte B760 GAMING X DDR4) and NIC (Realtek Gaming 2.5GbE Family Controller)
- I've tried 2 other NICs, but unfortunately they were all variations of Realtek boards (but same issue)
- Unlikely to be CPU or other bottleneck with Intel i7-13700KF, 64GB RAM and Mushkin MKNSSDTS1TB-D8 Tempest 1TB SSD
- Replaced cables and tried directly through ONT
- Setup local iPerf server to do testing and same packet loss
- Reset the network adapters on Windows 11
- Turned off security virtualization/hypervisor platform
- Fibre provider has replaced ONT and re-spliced into new PON - no difference (but considering the above, unlikely to be that)
- ISP has been unable to pick up any routing or capacity issues their side
- Tested in "clean boot" mode - no change
Unfortunately I've been unable to test in Safe Mode due to the Realtek drivers not supporting safe mode, but I did a complete clean install and even with the bare minimum there's no change. I can only think that there's a driver issue or some fundamental issue in Windows 11 I'm missing?
Below is an iperf from Windows 11, and then using Ubuntu to the same server, a few minutes apart:
iperf3.exe -4 -V -t 30 -O 3 -u -b 400M -l 1440 -R -c *******
iperf 3.15
CYGWIN_NT-10.0-22621 PC 3.4.9-1.x86_64 2023-09-06 11:19 UTC x86_64
Control connection MSS 1460
Time: Wed, 15 Nov 2023 12:39:34 GMT
Connecting to host *******, port 5201
Reverse mode, remote host ******* is sending
Target Bitrate: 400000000
[ 5] local 192.168.1.252 port 64574 connected to 196.******* port 5201
Starting Test: protocol: UDP, 1 streams, 1440 byte blocks, omitting 3 seconds, 30 second test, tos 0
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-1.00 sec 47.5 MBytes 399 Mbits/sec 0.021 ms 1780/36392 (4.9%) (omitted)
[ 5] 1.00-2.00 sec 47.6 MBytes 399 Mbits/sec 0.021 ms 91/34724 (0.26%) (omitted)
[ 5] 2.00-3.00 sec 46.7 MBytes 392 Mbits/sec 0.024 ms 720/34722 (2.1%) (omitted)
[ 5] 0.00-1.00 sec 47.6 MBytes 399 Mbits/sec 0.062 ms 53/34699 (0.15%)
[ 5] 1.00-2.00 sec 47.1 MBytes 395 Mbits/sec 0.059 ms 438/34748 (1.3%)
[ 5] 2.00-3.00 sec 47.2 MBytes 396 Mbits/sec 0.048 ms 323/34727 (0.93%)
[ 5] 3.00-4.00 sec 47.4 MBytes 398 Mbits/sec 0.056 ms 195/34718 (0.56%)
[ 5] 4.00-5.00 sec 47.6 MBytes 399 Mbits/sec 0.059 ms 69/34722 (0.2%)
[ 5] 5.00-6.00 sec 42.5 MBytes 357 Mbits/sec 0.052 ms 3774/34723 (11%)
[ 5] 6.00-7.00 sec 32.5 MBytes 272 Mbits/sec 0.053 ms 11087/34723 (32%)
[ 5] 7.00-8.00 sec 37.5 MBytes 314 Mbits/sec 0.050 ms 7432/34723 (21%)
[ 5] 8.00-9.00 sec 41.0 MBytes 344 Mbits/sec 0.038 ms 4821/34711 (14%)
[ 5] 9.00-10.00 sec 41.9 MBytes 351 Mbits/sec 0.051 ms 4241/34737 (12%)
[ 5] 10.00-11.00 sec 42.4 MBytes 356 Mbits/sec 0.048 ms 3836/34723 (11%)
[ 5] 11.00-12.00 sec 42.1 MBytes 353 Mbits/sec 0.037 ms 4072/34725 (12%)
[ 5] 12.00-13.00 sec 41.4 MBytes 347 Mbits/sec 0.041 ms 4586/34723 (13%)
[ 5] 13.00-14.00 sec 41.2 MBytes 346 Mbits/sec 0.037 ms 4716/34726 (14%)
[ 5] 14.00-15.00 sec 43.0 MBytes 360 Mbits/sec 0.041 ms 3440/34722 (9.9%)
[ 5] 15.00-16.00 sec 43.1 MBytes 362 Mbits/sec 0.068 ms 3314/34712 (9.5%)
[ 5] 16.00-17.00 sec 45.1 MBytes 378 Mbits/sec 0.039 ms 1895/34733 (5.5%)
[ 5] 17.00-18.00 sec 45.1 MBytes 379 Mbits/sec 0.026 ms 1865/34730 (5.4%)
[ 5] 18.00-19.01 sec 45.8 MBytes 382 Mbits/sec 0.028 ms 1273/34649 (3.7%)
[ 5] 19.01-20.00 sec 46.0 MBytes 388 Mbits/sec 0.028 ms 1337/34797 (3.8%)
[ 5] 20.00-21.00 sec 45.4 MBytes 381 Mbits/sec 0.025 ms 1670/34729 (4.8%)
[ 5] 21.00-22.00 sec 35.6 MBytes 299 Mbits/sec 0.023 ms 8765/34722 (25%)
[ 5] 22.00-23.00 sec 39.2 MBytes 329 Mbits/sec 0.024 ms 6169/34722 (18%)
[ 5] 23.00-24.00 sec 39.6 MBytes 332 Mbits/sec 0.043 ms 5871/34731 (17%)
[ 5] 24.00-25.00 sec 38.7 MBytes 325 Mbits/sec 0.023 ms 6504/34704 (19%)
[ 5] 25.00-26.00 sec 39.9 MBytes 335 Mbits/sec 0.046 ms 5654/34737 (16%)
[ 5] 26.00-27.00 sec 40.0 MBytes 336 Mbits/sec 0.049 ms 5570/34722 (16%)
[ 5] 27.00-28.00 sec 38.3 MBytes 322 Mbits/sec 0.069 ms 6805/34722 (20%)
[ 5] 28.00-29.00 sec 40.2 MBytes 337 Mbits/sec 0.045 ms 5445/34722 (16%)
[ 5] 29.00-30.00 sec 35.5 MBytes 298 Mbits/sec 0.056 ms 8863/34723 (26%)
- - - - - - - - - - - - - - - - - - - - - - - - -
Test Complete. Summary Results:
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-30.07 sec 1.40 GBytes 400 Mbits/sec 0.000 ms 0/0 (0%) sender
[SUM] 0.0-30.1 sec 31 datagrams received out-of-order
[ 5] 0.00-30.00 sec 1.23 GBytes 352 Mbits/sec 0.056 ms 124083/1041705 (12%) receiver
iperf Done.
Ubuntu:
iperf3 -4 -V -t 30 -O 3 -u -b 400M -l 1440 -R -c *******
iperf 3.9
Linux ubuntu 6.2.0-26-generic #26~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Jul 13 16:27:29 UTC 2 x86_64
Control connection MSS 1448
Time: Wed, 15 Nov 2023 14:30:09 GMT
Connecting to host *******, port 5201
Reverse mode, remote host ********* is sending
Cookie: *********
Target Bitrate: 400000000
[ 5] local 192.168.1.252 port 44626 connected to 196.******** port 5201
Starting Test: protocol: UDP, 1 streams, 1440 byte blocks, omitting 3 seconds, 30 second test, tos 0
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-1.00 sec 47.8 MBytes 401 Mbits/sec 0.014 ms 1313/36118 (3.6%) (omitted)
[ 5] 1.00-2.00 sec 47.7 MBytes 400 Mbits/sec 0.017 ms 0/34722 (0%) (omitted)
[ 5] 2.00-3.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 0/34723 (0%) (omitted)
[ 5] 0.00-1.00 sec 47.7 MBytes 400 Mbits/sec 0.015 ms 0/34722 (0%)
[ 5] 1.00-2.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 0/34722 (0%)
[ 5] 2.00-3.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 3.00-4.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34723 (0%)
[ 5] 4.00-5.00 sec 47.6 MBytes 399 Mbits/sec 0.027 ms 46/34694 (0.13%)
[ 5] 5.00-6.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34750 (0%)
[ 5] 6.00-7.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 0/34722 (0%)
[ 5] 7.00-8.00 sec 43.3 MBytes 363 Mbits/sec 0.011 ms 0/31548 (0%)
[ 5] 8.00-9.00 sec 52.0 MBytes 437 Mbits/sec 0.014 ms 0/37896 (0%)
[ 5] 9.00-10.00 sec 47.6 MBytes 400 Mbits/sec 0.016 ms 35/34723 (0.1%)
[ 5] 10.00-11.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 11.00-12.00 sec 47.7 MBytes 400 Mbits/sec 0.010 ms 0/34722 (0%)
[ 5] 12.00-13.00 sec 47.7 MBytes 400 Mbits/sec 0.015 ms 0/34722 (0%)
[ 5] 13.00-14.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 14.00-15.00 sec 47.3 MBytes 397 Mbits/sec 0.014 ms 244/34723 (0.7%)
[ 5] 15.00-16.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 16.00-17.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 0/34723 (0%)
[ 5] 17.00-18.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34721 (0%)
[ 5] 18.00-19.00 sec 47.6 MBytes 400 Mbits/sec 0.019 ms 44/34723 (0.13%)
[ 5] 19.00-20.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 0/34722 (0%)
[ 5] 20.00-21.00 sec 47.7 MBytes 400 Mbits/sec 0.015 ms 0/34722 (0%)
[ 5] 21.00-22.00 sec 47.7 MBytes 400 Mbits/sec 0.012 ms 0/34722 (0%)
[ 5] 22.00-23.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 9/34723 (0.026%)
[ 5] 23.00-24.00 sec 47.7 MBytes 400 Mbits/sec 0.013 ms 0/34722 (0%)
[ 5] 24.00-25.00 sec 47.6 MBytes 399 Mbits/sec 0.026 ms 73/34708 (0.21%)
[ 5] 25.00-26.00 sec 47.7 MBytes 400 Mbits/sec 0.015 ms 0/34737 (0%)
[ 5] 26.00-27.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 27.00-28.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 28.00-29.00 sec 47.7 MBytes 400 Mbits/sec 0.014 ms 0/34722 (0%)
[ 5] 29.00-30.00 sec 47.7 MBytes 400 Mbits/sec 0.017 ms 0/34722 (0%)
- - - - - - - - - - - - - - - - - - - - - - - - -
Test Complete. Summary Results:
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-30.06 sec 1.40 GBytes 400 Mbits/sec 0.000 ms 0/1042325 (0%) sender
[SUM] 0.0-30.1 sec 25 datagrams received out-of-order
[ 5] 0.00-30.00 sec 1.40 GBytes 400 Mbits/sec 0.017 ms 451/1041666 (0.043%) receiver
iperf Done.
Any suggestions on the cause and how to resolve?
