FWIW after about 24hr of use, the recent mac802011 patches are an improvement (but the lag and packet loss I saw before these patches was never as bad as others observed).
Is there a way to disable/enable "air time fairness" at runtime? Looking at this thread it does not look like there anything I can adjust/tune at run time.
If I run a simultaneous iperf (or netperf) from two different wifi clients on the same band/ssid, I've observed a "faster client" (farther from the AP but still the fastest client on the AP) dropping in speed from 200+ mps down to 5 mbps during the test. The slower client (closer the AP) stays relatively constant at ~ 160 mbps. Simultaneous irtt during the combined iperf/netperf test from either client to the local server(s) (a wired connection to the AP) during the test shows good rtt and no packet loss. Equal distant from the AP, the faster client can do ~500 mbps while the slower can do ~180 mbps.
I'm running the tests with the network in use so results vary but I do see one client "suppressing" others more than I can justify by my WAN connection (30 mbps down, ~3 mbps up).
EDIT additional testing running irtt simultaneous with netperf on the client being slowed down (netperf also run simultaneously from a second unaffected client) shows significant rtt (> 1 s).
output below (irtt & netperf started on the affected client about the same time, netperf started on the second client as indicated in the output below.
nmba [10] $ ./go/bin/irtt client XXX.XXX.45.26
[Connecting] connecting to XXX.XXX.45.26
[XXX.XXX.45.26:2112] [Connected] connection established
seq=0 rtt=3.03ms rd=332.8ms sd=-329.8ms ipdv=n/a
seq=1 rtt=3.26ms rd=332ms sd=-328.7ms ipdv=227µs
seq=2 rtt=2.07ms rd=331.7ms sd=-329.7ms ipdv=1.2ms
seq=4 rtt=192ms rd=499.3ms sd=-307.2ms ipdv=n/a
seq=5 rtt=91.57ms rd=344.2ms sd=-252.6ms ipdv=100.5ms
seq=6 rtt=143.8ms rd=344.3ms sd=-200.4ms ipdv=52.25ms
seq=7 rtt=26.02ms rd=348ms sd=-322ms ipdv=117.8ms
seq=8 rtt=10.05ms rd=338.5ms sd=-328.4ms ipdv=15.97ms
seq=9 rtt=21.68ms rd=342.9ms sd=-321.2ms ipdv=11.63ms
seq=10 rtt=22.79ms rd=337.8ms sd=-315ms ipdv=1.11ms
seq=11 rtt=16.98ms rd=336.9ms sd=-319.9ms ipdv=5.81ms
seq=12 rtt=10.09ms rd=337.9ms sd=-327.9ms ipdv=6.89ms
seq=13 rtt=5.18ms rd=334.5ms sd=-329.3ms ipdv=4.91ms
seq=14 rtt=9.67ms rd=339ms sd=-329.4ms ipdv=4.48ms
seq=15 rtt=10.95ms rd=334.1ms sd=-323.2ms ipdv=1.28ms
seq=16 rtt=2.72ms rd=332.7ms sd=-330ms ipdv=8.23ms
seq=17 rtt=9.02ms rd=335.9ms sd=-326.9ms ipdv=6.31ms
seq=18 rtt=4.52ms rd=333.4ms sd=-328.9ms ipdv=4.5ms
seq=19 rtt=5.39ms rd=335.1ms sd=-329.7ms ipdv=870µs
seq=20 rtt=12.17ms rd=334.7ms sd=-322.6ms ipdv=6.78ms
seq=21 rtt=170.7ms rd=337.2ms sd=-166.5ms ipdv=158.5ms
seq=22 rtt=11.5ms rd=337.1ms sd=-325.6ms ipdv=159.2ms
seq=23 rtt=436.1ms rd=334.4ms sd=101.7ms ipdv=424.6ms
seq=24 rtt=631ms rd=345ms sd=286ms ipdv=194.9ms
seq=25 rtt=10.69ms rd=335.1ms sd=-324.4ms ipdv=620.3ms
seq=26 rtt=518.5ms rd=340.6ms sd=177.9ms ipdv=507.8ms
seq=27 rtt=11.68ms rd=337.1ms sd=-325.4ms ipdv=506.8ms
seq=28 rtt=208.4ms rd=339.1ms sd=-130.7ms ipdv=196.7ms
seq=29 rtt=117.3ms rd=336.5ms sd=-219.2ms ipdv=91.08ms
seq=30 rtt=646.4ms rd=340.4ms sd=306ms ipdv=529.2ms
seq=31 rtt=72.32ms rd=349.6ms sd=-277.3ms ipdv=574.1ms
seq=32 rtt=43.87ms rd=336.8ms sd=-292.9ms ipdv=28.46ms
seq=33 rtt=7.72ms rd=338.4ms sd=-330.7ms ipdv=36.15ms
seq=34 rtt=416.4ms rd=343.5ms sd=72.82ms ipdv=408.6ms
seq=35 rtt=4.89ms rd=333.8ms sd=-328.9ms ipdv=411.5ms
seq=36 rtt=39.52ms rd=335.4ms sd=-295.9ms ipdv=34.62ms
seq=37 rtt=44.65ms rd=344.2ms sd=-299.6ms ipdv=5.13ms
seq=38 rtt=15.45ms rd=343.1ms sd=-327.6ms ipdv=29.19ms
seq=39 rtt=6.77ms rd=336.6ms sd=-329.9ms ipdv=8.69ms
seq=40 rtt=279.5ms rd=346.2ms sd=-66.77ms ipdv=272.7ms
seq=41 rtt=64.47ms rd=337.7ms sd=-273.2ms ipdv=215ms
seq=42 rtt=1.21s rd=335.7ms sd=875.6ms ipdv=1.15s
seq=43 rtt=397.4ms rd=333.4ms sd=64.04ms ipdv=813.9ms
seq=44 rtt=416.3ms rd=335.1ms sd=81.23ms ipdv=18.93ms
seq=45 rtt=428.1ms rd=335.4ms sd=92.66ms ipdv=11.76ms
seq=46 rtt=181.4ms rd=334.3ms sd=-152.9ms ipdv=246.7ms
seq=47 rtt=371.3ms rd=334.4ms sd=36.86ms ipdv=189.9ms
seq=48 rtt=81.52ms rd=339.7ms sd=-258.2ms ipdv=289.8ms
seq=49 rtt=330.7ms rd=335ms sd=-4.23ms ipdv=249.2ms
seq=51 rtt=524.7ms rd=333ms sd=191.7ms ipdv=n/a
seq=52 rtt=306.7ms rd=336.6ms sd=-29.89ms ipdv=218.1ms
seq=53 rtt=50.8ms rd=337.5ms sd=-286.7ms ipdv=255.9ms
seq=54 rtt=113.5ms rd=333.9ms sd=-220.4ms ipdv=62.68ms
seq=55 rtt=199.2ms rd=335.4ms sd=-136.1ms ipdv=85.74ms
seq=56 rtt=721.9ms rd=337.9ms sd=384ms ipdv=522.6ms
seq=57 rtt=6.14ms rd=336.2ms sd=-330.1ms ipdv=715.7ms
seq=58 rtt=13.66ms rd=334.1ms sd=-320.4ms ipdv=7.52ms
[XXX.XXX.45.26:2112] [WaitForPackets] waiting 3.63s for final packets
seq=59 rtt=322.7ms rd=335.3ms sd=-12.57ms ipdv=309.1ms
Min Mean Median Max Stddev
--- ---- ------ --- ------
RTT 2.07ms 173.1ms 47.72ms 1.21s 239.8ms
send delay -330.7ms -167.2ms -294.4ms 875.6ms 240.4ms
receive delay 331.7ms 340.3ms 336.6ms 499.3ms 21.64ms
IPDV (jitter) 227µs 198.3ms 91.08ms 1.15s 250ms
send IPDV 55µs 195.9ms 84.27ms 1.15s 250.3ms
receive IPDV 10.4µs 6.47ms 2.63ms 155.1ms 20.66ms
send call time 30.5µs 123µs 498µs 84.1µs
timer error 102µs 1.29ms 3.78ms 977µs
server proc. time 6.04µs 11.1µs 26.9µs 3.29µs
duration: 1m3s (wait 3.63s)
packets sent/received: 60/58 (3.33% loss)
server packets received: 58/60 (3.33%/0.00% loss up/down)
bytes sent/received: 3600/3480
send/receive rate: 488 bps / 469 bps
packet length: 60 bytes
timer stats: 0/60 (0.00%) missed, 0.13% error
### netperf output below approx. simultaneous started with irtt output above ###
nmba [63] $ netperf -l 60 -D 1s -H XXX.XXX.45.26
MIGRATED TCP STREAM TEST from (null) (XXX.XXX.0.0) port 0 AF_INET to (null) () port 0 AF_INET : demo
Interim result: 67.70 10^6bits/s over 2.494 seconds ending at 1597509441.475
Interim result: 221.78 10^6bits/s over 1.012 seconds ending at 1597509442.486
Interim result: 250.37 10^6bits/s over 1.005 seconds ending at 1597509443.492
Interim result: 237.70 10^6bits/s over 1.041 seconds ending at 1597509444.533
Interim result: 260.36 10^6bits/s over 1.011 seconds ending at 1597509445.544
Interim result: 225.17 10^6bits/s over 1.160 seconds ending at 1597509446.703
Interim result: 241.81 10^6bits/s over 1.041 seconds ending at 1597509447.744
Interim result: 246.44 10^6bits/s over 1.013 seconds ending at 1597509448.757
Interim result: 182.91 10^6bits/s over 1.399 seconds ending at 1597509450.155
Interim result: 230.01 10^6bits/s over 1.012 seconds ending at 1597509451.167
Interim result: 167.48 10^6bits/s over 1.377 seconds ending at 1597509452.545
Interim result: 185.26 10^6bits/s over 1.002 seconds ending at 1597509453.547
Interim result: 198.51 10^6bits/s over 1.014 seconds ending at 1597509454.561
Interim result: 177.08 10^6bits/s over 1.113 seconds ending at 1597509455.674
### started netperf on second client approx. here ###
### no output was redacted here, just these comments inserted ###
Interim result: 7.45 10^6bits/s over 23.779 seconds ending at 1597509479.453
Interim result: 0.38 10^6bits/s over 19.532 seconds ending at 1597509498.986
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
131072 131072 131072 63.88 53.30
### netperf output from second client ###
(p383.mkl) [16] $ netperf -l 60 -D 1s -H XXX.XXX.45.26
MIGRATED TCP STREAM TEST from XXX.XXX.0.0 (XXX.XXX.0.0) port 0 AF_INET to XXX.XXX.45.26 () port 0 AF_INET : demo
Interim result: 77.73 10^6bits/s over 2.054 seconds ending at 1597509457.651
Interim result: 145.66 10^6bits/s over 1.028 seconds ending at 1597509458.679
Interim result: 156.10 10^6bits/s over 1.019 seconds ending at 1597509459.697
Interim result: 148.71 10^6bits/s over 1.050 seconds ending at 1597509460.747
Interim result: 154.39 10^6bits/s over 1.009 seconds ending at 1597509461.755
Interim result: 158.68 10^6bits/s over 1.014 seconds ending at 1597509462.770
Interim result: 149.30 10^6bits/s over 1.062 seconds ending at 1597509463.832
Interim result: 159.60 10^6bits/s over 1.027 seconds ending at 1597509464.859
Interim result: 163.26 10^6bits/s over 1.053 seconds ending at 1597509465.911
Interim result: 164.67 10^6bits/s over 1.017 seconds ending at 1597509466.928
Interim result: 147.25 10^6bits/s over 1.118 seconds ending at 1597509468.046
Interim result: 162.72 10^6bits/s over 1.010 seconds ending at 1597509469.057
Interim result: 157.13 10^6bits/s over 1.036 seconds ending at 1597509470.093
Interim result: 150.34 10^6bits/s over 1.044 seconds ending at 1597509471.137
Interim result: 156.09 10^6bits/s over 1.039 seconds ending at 1597509472.176
Interim result: 171.78 10^6bits/s over 1.038 seconds ending at 1597509473.214
Interim result: 156.11 10^6bits/s over 1.101 seconds ending at 1597509474.315
Interim result: 144.44 10^6bits/s over 1.081 seconds ending at 1597509475.396
Interim result: 149.38 10^6bits/s over 1.057 seconds ending at 1597509476.453
Interim result: 167.97 10^6bits/s over 1.051 seconds ending at 1597509477.504
Interim result: 166.29 10^6bits/s over 1.041 seconds ending at 1597509478.545
Interim result: 144.20 10^6bits/s over 1.153 seconds ending at 1597509479.699
Interim result: 157.44 10^6bits/s over 1.037 seconds ending at 1597509480.736
Interim result: 163.50 10^6bits/s over 1.013 seconds ending at 1597509481.749
Interim result: 158.93 10^6bits/s over 1.029 seconds ending at 1597509482.779
Interim result: 158.69 10^6bits/s over 1.061 seconds ending at 1597509483.840
Interim result: 168.49 10^6bits/s over 1.009 seconds ending at 1597509484.849
Interim result: 164.34 10^6bits/s over 1.056 seconds ending at 1597509485.905
Interim result: 168.65 10^6bits/s over 1.049 seconds ending at 1597509486.954
Interim result: 170.73 10^6bits/s over 1.030 seconds ending at 1597509487.984
Interim result: 159.83 10^6bits/s over 1.068 seconds ending at 1597509489.051
Interim result: 167.36 10^6bits/s over 1.053 seconds ending at 1597509490.104
Interim result: 169.60 10^6bits/s over 1.056 seconds ending at 1597509491.161
Interim result: 168.03 10^6bits/s over 1.009 seconds ending at 1597509492.170
Interim result: 163.91 10^6bits/s over 1.025 seconds ending at 1597509493.195
Interim result: 164.34 10^6bits/s over 1.068 seconds ending at 1597509494.263
Interim result: 169.86 10^6bits/s over 1.056 seconds ending at 1597509495.319
Interim result: 170.20 10^6bits/s over 1.045 seconds ending at 1597509496.364
Interim result: 161.42 10^6bits/s over 1.070 seconds ending at 1597509497.434
Interim result: 175.67 10^6bits/s over 1.065 seconds ending at 1597509498.499
Interim result: 174.19 10^6bits/s over 1.008 seconds ending at 1597509499.507
Interim result: 166.29 10^6bits/s over 1.048 seconds ending at 1597509500.554
Interim result: 171.50 10^6bits/s over 1.025 seconds ending at 1597509501.579
Interim result: 179.17 10^6bits/s over 1.013 seconds ending at 1597509502.592
Interim result: 166.87 10^6bits/s over 1.074 seconds ending at 1597509503.666
Interim result: 160.98 10^6bits/s over 1.056 seconds ending at 1597509504.722
Interim result: 170.06 10^6bits/s over 1.041 seconds ending at 1597509505.763
Interim result: 162.35 10^6bits/s over 1.087 seconds ending at 1597509506.850
Interim result: 168.24 10^6bits/s over 1.064 seconds ending at 1597509507.914
Interim result: 166.26 10^6bits/s over 1.048 seconds ending at 1597509508.962
Interim result: 168.52 10^6bits/s over 1.046 seconds ending at 1597509510.008
Interim result: 170.65 10^6bits/s over 1.038 seconds ending at 1597509511.046
Interim result: 172.41 10^6bits/s over 1.034 seconds ending at 1597509512.080
Interim result: 167.24 10^6bits/s over 1.031 seconds ending at 1597509513.110
Interim result: 165.13 10^6bits/s over 1.013 seconds ending at 1597509514.123
Interim result: 171.17 10^6bits/s over 1.048 seconds ending at 1597509515.172
Interim result: 189.94 10^6bits/s over 0.426 seconds ending at 1597509515.597
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
131072 16384 16384 60.19 159.52