To clarify, my tests were not run during backup activity. I only brought up the part about backups to head off any comments about my speeds being "good enough for internet speeds."
Just for reference, I re-installed @quarky's NSS enabled build (17.01-SNAPSHOT r4075-54fc4f9050) which I had been testing some time ago. I still see the same excellent ethernet speeds, but WiFi is measurably better in terms of bandwidth. I ran the WiFi tests for 30 seconds to allow speeds to stabilize:
$ iperf3 -c 192.168.45.5 -i1 -V -t 30
Connecting to host 192.168.45.5, port 5201
TCP MSS: 1448 (default)
[ 5] local 192.168.45.145 port 53961 connected to 192.168.45.5 port 5201
Starting Test: protocol: TCP, 1 streams, 131072 byte blocks, omitting 0 seconds, 30 second test, tos 0
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 18.7 MBytes 157 Mbits/sec
[ 5] 1.00-2.00 sec 34.8 MBytes 292 Mbits/sec
[ 5] 2.00-3.00 sec 43.2 MBytes 362 Mbits/sec
[ 5] 3.00-4.00 sec 44.4 MBytes 373 Mbits/sec
[ 5] 4.00-5.00 sec 45.5 MBytes 382 Mbits/sec
[ 5] 5.00-6.00 sec 48.9 MBytes 410 Mbits/sec
[ 5] 6.00-7.00 sec 50.0 MBytes 419 Mbits/sec
[ 5] 7.00-8.00 sec 50.4 MBytes 423 Mbits/sec
[ 5] 8.00-9.00 sec 50.1 MBytes 420 Mbits/sec
[ 5] 9.00-10.00 sec 51.5 MBytes 432 Mbits/sec
[ 5] 10.00-11.00 sec 51.3 MBytes 430 Mbits/sec
[ 5] 11.00-12.00 sec 51.4 MBytes 431 Mbits/sec
[ 5] 12.00-13.00 sec 53.5 MBytes 449 Mbits/sec
[ 5] 13.00-14.00 sec 54.0 MBytes 453 Mbits/sec
[ 5] 14.00-15.00 sec 50.8 MBytes 426 Mbits/sec
[ 5] 15.00-16.00 sec 51.9 MBytes 435 Mbits/sec
[ 5] 16.00-17.00 sec 52.8 MBytes 443 Mbits/sec
[ 5] 17.00-18.00 sec 53.0 MBytes 444 Mbits/sec
[ 5] 18.00-19.00 sec 53.7 MBytes 451 Mbits/sec
[ 5] 19.00-20.00 sec 51.2 MBytes 429 Mbits/sec
[ 5] 20.00-21.00 sec 50.9 MBytes 427 Mbits/sec
[ 5] 21.00-22.00 sec 51.9 MBytes 435 Mbits/sec
[ 5] 22.00-23.00 sec 51.6 MBytes 433 Mbits/sec
[ 5] 23.00-24.00 sec 50.9 MBytes 427 Mbits/sec
[ 5] 24.00-25.00 sec 51.2 MBytes 429 Mbits/sec
[ 5] 25.00-26.00 sec 51.6 MBytes 433 Mbits/sec
[ 5] 26.00-27.00 sec 53.5 MBytes 449 Mbits/sec
[ 5] 27.00-28.00 sec 52.8 MBytes 443 Mbits/sec
[ 5] 28.00-29.00 sec 53.3 MBytes 447 Mbits/sec
[ 5] 29.00-30.00 sec 52.4 MBytes 440 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
Test Complete. Summary Results:
[ ID] Interval Transfer Bitrate
[ 5] 0.00-30.00 sec 1.45 GBytes 414 Mbits/sec sender
[ 5] 0.00-30.05 sec 1.45 GBytes 413 Mbits/sec receiver
CPU Utilization: local/sender 30.9% (4.0%u/26.8%s), remote/receiver 3.3% (0.4%u/2.8%s)
$ iperf3 -c 192.168.45.5 -i1 -V -t 30 -R
Connecting to host 192.168.45.5, port 5201
Reverse mode, remote host 192.168.45.5 is sending
TCP MSS: 1448 (default)
[ 5] local 192.168.45.145 port 53964 connected to 192.168.45.5 port 5201
Starting Test: protocol: TCP, 1 streams, 131072 byte blocks, omitting 0 seconds, 30 second test, tos 0
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 40.8 MBytes 342 Mbits/sec
[ 5] 1.00-2.00 sec 49.0 MBytes 411 Mbits/sec
[ 5] 2.00-3.00 sec 57.3 MBytes 481 Mbits/sec
[ 5] 3.00-4.00 sec 61.1 MBytes 513 Mbits/sec
[ 5] 4.00-5.00 sec 64.4 MBytes 541 Mbits/sec
[ 5] 5.00-6.00 sec 67.0 MBytes 562 Mbits/sec
[ 5] 6.00-7.00 sec 69.1 MBytes 580 Mbits/sec
[ 5] 7.00-8.00 sec 69.6 MBytes 584 Mbits/sec
[ 5] 8.00-9.00 sec 69.9 MBytes 587 Mbits/sec
[ 5] 9.00-10.00 sec 73.0 MBytes 612 Mbits/sec
[ 5] 10.00-11.00 sec 75.1 MBytes 630 Mbits/sec
[ 5] 11.00-12.00 sec 76.1 MBytes 638 Mbits/sec
[ 5] 12.00-13.00 sec 77.4 MBytes 649 Mbits/sec
[ 5] 13.00-14.00 sec 77.7 MBytes 652 Mbits/sec
[ 5] 14.00-15.00 sec 80.5 MBytes 675 Mbits/sec
[ 5] 15.00-16.00 sec 81.1 MBytes 680 Mbits/sec
[ 5] 16.00-17.00 sec 81.3 MBytes 682 Mbits/sec
[ 5] 17.00-18.00 sec 80.0 MBytes 671 Mbits/sec
[ 5] 18.00-19.00 sec 82.5 MBytes 692 Mbits/sec
[ 5] 19.00-20.00 sec 83.3 MBytes 698 Mbits/sec
[ 5] 20.00-21.00 sec 84.9 MBytes 712 Mbits/sec
[ 5] 21.00-22.00 sec 85.8 MBytes 720 Mbits/sec
[ 5] 22.00-23.00 sec 85.4 MBytes 716 Mbits/sec
[ 5] 23.00-24.00 sec 56.8 MBytes 476 Mbits/sec
[ 5] 24.00-25.00 sec 53.0 MBytes 445 Mbits/sec
[ 5] 25.00-26.00 sec 56.6 MBytes 475 Mbits/sec
[ 5] 26.00-27.00 sec 62.6 MBytes 525 Mbits/sec
[ 5] 27.00-28.00 sec 66.6 MBytes 559 Mbits/sec
[ 5] 28.00-29.00 sec 69.0 MBytes 579 Mbits/sec
[ 5] 29.00-30.00 sec 71.3 MBytes 598 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
Test Complete. Summary Results:
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-30.03 sec 2.06 GBytes 589 Mbits/sec 1 sender
[ 5] 0.00-30.00 sec 2.06 GBytes 589 Mbits/sec receiver
My concern, and next step for testing, is that the WiFi driver in this build will exhibit significant wireless bufferbloat since it's not using the ath10k CT version that has WiFi bufferbloat enhancements.
** UPDATE **
Just ran an internet speed test and my results match the same up/down speeds that I receive on an ethernet connection. I haven't seen my download speed (420 Mbps down) reach and hold that speed on WiFi in a long time. Also, I did not see any alarming increase in ping times during that speed test, so immediate concern re: wireless bufferbloat is looking minimal at the moment.
** UPDATE 2 **
The CPU governor is ondemand by default, so for giggles I am going to try to set it to performance and run the tests again...