iwlwifi(4) and AX210 performance as receiver and sender.
Date: Mon, 21 Apr 2025 20:40:57 UTC
First, sorry if the experiment is not accurate or even doesn't make sense. Performance test is hard, anyway. I found that it seems the iwlwifi(4) performance has a noticeable difference when acting as iperf receiver or sender. My setup is straightforward: laptop - AP - router. Laptop: AX210 with iwlwifi(4) Router: Intel I226-V with igc(4) When iwlwifi(4) being the receiver: laptop: Accepted connection from 192.168.169.250, port 29906 [ 5] local 192.168.169.39 port 5201 connected to 192.168.169.250 port 24810 [ ID] Interval Transfer Bitrate [ 5] 0.00-1.05 sec 54.8 MBytes 439 Mbits/sec [ 5] 1.05-2.00 sec 59.0 MBytes 517 Mbits/sec [ 5] 2.00-3.00 sec 63.2 MBytes 531 Mbits/sec [ 5] 3.00-4.01 sec 64.6 MBytes 536 Mbits/sec [ 5] 4.01-5.01 sec 62.4 MBytes 527 Mbits/sec [ 5] 5.01-6.02 sec 64.0 MBytes 530 Mbits/sec [ 5] 6.02-7.00 sec 61.8 MBytes 528 Mbits/sec [ 5] 7.00-8.00 sec 62.5 MBytes 524 Mbits/sec [ 5] 8.00-9.02 sec 60.4 MBytes 497 Mbits/sec [ 5] 9.02-10.01 sec 61.0 MBytes 517 Mbits/sec - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate [ 5] 0.00-10.01 sec 614 MBytes 514 Mbits/sec receiver router: [ 5] local 192.168.169.250 port 24810 connected to 192.168.169.39 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.01 sec 53.5 MBytes 444 Mbits/sec 0 794 KBytes [ 5] 1.01-2.02 sec 62.6 MBytes 518 Mbits/sec 0 1.07 MBytes [ 5] 2.02-3.03 sec 63.2 MBytes 527 Mbits/sec 0 1.07 MBytes [ 5] 3.03-4.06 sec 66.2 MBytes 539 Mbits/sec 0 1.07 MBytes [ 5] 4.06-5.00 sec 59.0 MBytes 526 Mbits/sec 0 1.07 MBytes [ 5] 5.00-6.00 sec 63.0 MBytes 529 Mbits/sec 0 1.07 MBytes [ 5] 6.00-7.03 sec 65.2 MBytes 530 Mbits/sec 0 1.07 MBytes [ 5] 7.03-8.02 sec 61.9 MBytes 526 Mbits/sec 0 1.07 MBytes [ 5] 8.02-9.03 sec 59.2 MBytes 495 Mbits/sec 94 582 KBytes [ 5] 9.03-10.00 sec 60.4 MBytes 519 Mbits/sec 0 649 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 614 MBytes 515 Mbits/sec 94 sender [ 5] 0.00-10.01 sec 614 MBytes 514 Mbits/sec receiver When iwlwifi(4) being the sender: laptop: Connecting to host router, port 5201 [ 5] local 192.168.169.39 port 26748 connected to 192.168.169.250 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 16.4 MBytes 137 Mbits/sec 21 47.4 KBytes [ 5] 1.00-2.01 sec 18.4 MBytes 152 Mbits/sec 37 58.7 KBytes [ 5] 2.01-3.00 sec 16.4 MBytes 139 Mbits/sec 59 19.8 KBytes [ 5] 3.00-4.02 sec 19.4 MBytes 160 Mbits/sec 87 2.83 KBytes [ 5] 4.02-5.04 sec 15.1 MBytes 124 Mbits/sec 46 45.9 KBytes [ 5] 5.04-6.00 sec 15.1 MBytes 132 Mbits/sec 46 35.4 KBytes [ 5] 6.00-7.00 sec 14.9 MBytes 125 Mbits/sec 43 51.6 KBytes [ 5] 7.00-8.01 sec 15.6 MBytes 130 Mbits/sec 70 68.6 KBytes [ 5] 8.01-9.05 sec 17.2 MBytes 140 Mbits/sec 24 64.9 KBytes [ 5] 9.05-10.02 sec 17.8 MBytes 154 Mbits/sec 31 51.5 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.02 sec 166 MBytes 139 Mbits/sec 464 sender [ 5] 0.00-10.02 sec 166 MBytes 139 Mbits/sec receiver router: Accepted connection from 192.168.169.39, port 46082 [ 5] local 192.168.169.250 port 5201 connected to 192.168.169.39 port 16801 [ ID] Interval Transfer Bitrate [ 5] 0.00-1.01 sec 12.2 MBytes 102 Mbits/sec [ 5] 1.01-2.05 sec 15.5 MBytes 125 Mbits/sec [ 5] 2.05-3.00 sec 14.0 MBytes 123 Mbits/sec [ 5] 3.00-4.00 sec 15.2 MBytes 128 Mbits/sec [ 5] 4.00-5.03 sec 15.0 MBytes 122 Mbits/sec [ 5] 5.03-6.00 sec 17.0 MBytes 147 Mbits/sec [ 5] 6.00-7.01 sec 14.4 MBytes 120 Mbits/sec [ 5] 7.01-8.00 sec 15.5 MBytes 131 Mbits/sec [ 5] 8.00-9.02 sec 13.0 MBytes 107 Mbits/sec [ 5] 9.02-10.01 sec 15.0 MBytes 127 Mbits/sec - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate [ 5] 0.00-10.01 sec 147 MBytes 123 Mbits/sec receiver It seems that when being the sender, the performance is not very good compared with being the receiver. Note that the retry numbers are also much different. I haven't dug into the details right now, but I think it might be good to share this earlier. Let me know if you need more information or tests. Best, Li-Wen