Hi,
I'm having some issues on my 2.4GHz band (5GHz band works perfectly): it constantly switches between full throughput and a somewhat limited throughput, intermittently, affecting all connected devices simultaneously on the 2.4GHz band.
Switches seem to happen at constant rates, like ~13 seconds at low throughput and then ~7 seconds at high throughput, repeating infinitely.
I already tried to troubleshoot it, without any luck... Maybe someone have suggestions on what can be checked or tried.
My setup is the following:
- Router: AVM FRITZ!Box 7530
- OpenWRT: tried both latest 24 SNAPSHOT (r28200-c857145e03) and 23.05.3 versions
- Wireless firmware: tried NON CT, CT and CT FULL HTT firmwares (on both OpenWRT versions above)
This is a screenshot while running an iperf3 test, between PC and router running latest OpenWRT snapshot, with just a single WiFi interface configured on the 2.4GHz band, with a MAC filter to allow only PC connection and with 5GHz band disabled:
This is the router iperf3 output, from which it can be seen that the speed changes at regular intervals:
[ 5] local 192.168.1.1 port 5201 connected to 192.168.1.189 port 64890
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 2.12 MBytes 17.8 Mbits/sec
[ 5] 1.00-2.00 sec 896 KBytes 7.34 Mbits/sec
[ 5] 2.00-3.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 3.00-4.00 sec 6.38 MBytes 53.5 Mbits/sec
[ 5] 4.00-5.00 sec 8.25 MBytes 69.2 Mbits/sec
[ 5] 5.00-6.00 sec 9.75 MBytes 81.8 Mbits/sec
[ 5] 6.00-7.00 sec 8.62 MBytes 72.4 Mbits/sec
[ 5] 7.00-8.00 sec 9.38 MBytes 78.6 Mbits/sec
[ 5] 8.00-9.00 sec 10.8 MBytes 90.2 Mbits/sec
[ 5] 9.00-10.00 sec 10.0 MBytes 83.9 Mbits/sec
[ 5] 10.00-11.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 11.00-12.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 12.00-13.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 13.00-14.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 14.00-15.00 sec 512 KBytes 4.19 Mbits/sec
[ 5] 15.00-16.00 sec 1.00 MBytes 8.39 Mbits/sec
[ 5] 16.00-17.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 17.00-18.00 sec 896 KBytes 7.34 Mbits/sec
[ 5] 18.00-19.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 19.00-20.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 20.00-21.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 21.00-22.00 sec 1.12 MBytes 9.44 Mbits/sec
[ 5] 22.00-23.00 sec 3.12 MBytes 26.2 Mbits/sec
[ 5] 23.00-24.00 sec 10.9 MBytes 91.2 Mbits/sec
[ 5] 24.00-25.00 sec 8.62 MBytes 72.4 Mbits/sec
[ 5] 25.00-26.00 sec 9.00 MBytes 75.5 Mbits/sec
[ 5] 26.00-27.00 sec 9.12 MBytes 76.5 Mbits/sec
[ 5] 27.00-28.00 sec 8.12 MBytes 68.2 Mbits/sec
[ 5] 28.00-29.00 sec 8.88 MBytes 74.4 Mbits/sec
[ 5] 29.00-30.00 sec 7.50 MBytes 62.9 Mbits/sec
[ 5] 30.00-31.00 sec 1.62 MBytes 13.6 Mbits/sec
[ 5] 31.00-32.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 32.00-33.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 33.00-34.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 34.00-35.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 35.00-36.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 36.00-37.00 sec 1.62 MBytes 13.6 Mbits/sec
[ 5] 37.00-38.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 38.00-39.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 39.00-40.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 40.00-41.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 41.00-42.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 42.00-43.00 sec 2.00 MBytes 16.8 Mbits/sec
[ 5] 43.00-44.00 sec 2.25 MBytes 18.9 Mbits/sec
[ 5] 44.00-45.00 sec 4.88 MBytes 40.9 Mbits/sec
[ 5] 45.00-46.00 sec 10.2 MBytes 86.0 Mbits/sec
[ 5] 46.00-47.00 sec 5.38 MBytes 45.1 Mbits/sec
[ 5] 47.00-48.00 sec 7.88 MBytes 66.1 Mbits/sec
[ 5] 48.00-49.00 sec 7.00 MBytes 58.7 Mbits/sec
[ 5] 49.00-50.00 sec 9.88 MBytes 82.8 Mbits/sec
[ 5] 50.00-51.00 sec 3.88 MBytes 32.5 Mbits/sec
[ 5] 51.00-52.00 sec 1.62 MBytes 13.6 Mbits/sec
[ 5] 52.00-53.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 53.00-54.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 54.00-55.00 sec 1.12 MBytes 9.43 Mbits/sec
[ 5] 55.00-56.00 sec 1.62 MBytes 13.6 Mbits/sec
[ 5] 56.00-57.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 57.00-58.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 58.00-59.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 59.00-60.00 sec 2.00 MBytes 16.8 Mbits/sec
[ 5] 60.00-61.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 61.00-62.00 sec 384 KBytes 3.15 Mbits/sec
[ 5] 62.00-63.00 sec 1.62 MBytes 13.6 Mbits/sec
[ 5] 63.00-64.00 sec 8.62 MBytes 72.4 Mbits/sec
[ 5] 64.00-65.00 sec 10.5 MBytes 88.1 Mbits/sec
[ 5] 65.00-66.00 sec 9.12 MBytes 76.6 Mbits/sec
[ 5] 66.00-67.00 sec 9.62 MBytes 80.7 Mbits/sec
[ 5] 67.00-68.00 sec 10.2 MBytes 86.0 Mbits/sec
[ 5] 68.00-69.00 sec 9.00 MBytes 75.5 Mbits/sec
[ 5] 69.00-70.00 sec 9.88 MBytes 82.8 Mbits/sec
[ 5] 70.00-71.00 sec 2.62 MBytes 22.0 Mbits/sec
[ 5] 71.00-72.00 sec 1.00 MBytes 8.39 Mbits/sec
[ 5] 72.00-73.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 73.00-74.00 sec 1.00 MBytes 8.39 Mbits/sec
[ 5] 74.00-75.00 sec 1.12 MBytes 9.44 Mbits/sec
[ 5] 75.00-76.00 sec 1.62 MBytes 13.6 Mbits/sec
[ 5] 76.00-77.00 sec 1.12 MBytes 9.43 Mbits/sec
[ 5] 77.00-78.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 78.00-79.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 79.00-80.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 80.00-81.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 81.00-82.00 sec 128 KBytes 1.05 Mbits/sec
[ 5] 82.00-83.00 sec 1.00 MBytes 8.39 Mbits/sec
[ 5] 83.00-84.00 sec 6.50 MBytes 54.5 Mbits/sec
[ 5] 84.00-85.00 sec 6.38 MBytes 53.5 Mbits/sec
[ 5] 85.00-86.00 sec 4.88 MBytes 40.9 Mbits/sec
[ 5] 86.00-87.00 sec 6.00 MBytes 50.3 Mbits/sec
[ 5] 87.00-88.00 sec 4.50 MBytes 37.7 Mbits/sec
[ 5] 88.00-89.00 sec 5.50 MBytes 46.1 Mbits/sec
[ 5] 89.00-90.00 sec 9.50 MBytes 79.7 Mbits/sec
[ 5] 90.00-91.00 sec 10.0 MBytes 83.9 Mbits/sec
[ 5] 91.00-92.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 92.00-93.00 sec 1.00 MBytes 8.39 Mbits/sec
[ 5] 93.00-94.00 sec 896 KBytes 7.34 Mbits/sec
[ 5] 94.00-95.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 95.00-96.00 sec 1.12 MBytes 9.44 Mbits/sec
[ 5] 96.00-97.00 sec 1.00 MBytes 8.39 Mbits/sec
[ 5] 97.00-98.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 98.00-99.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 99.00-100.00 sec 1.25 MBytes 10.5 Mbits/sec
[ 5] 100.00-101.00 sec 1.50 MBytes 12.6 Mbits/sec
[ 5] 101.00-102.00 sec 1.12 MBytes 9.44 Mbits/sec
[ 5] 102.00-103.00 sec 1.38 MBytes 11.5 Mbits/sec
[ 5] 103.00-104.00 sec 2.12 MBytes 17.8 Mbits/sec
[ 5] 104.00-105.00 sec 3.88 MBytes 32.5 Mbits/sec
[ 5] 105.00-106.00 sec 9.00 MBytes 75.5 Mbits/sec
[ 5] 106.00-107.00 sec 10.1 MBytes 84.9 Mbits/sec
[ 5] 107.00-108.00 sec 10.4 MBytes 87.0 Mbits/sec
[ 5] 108.00-109.00 sec 9.12 MBytes 76.5 Mbits/sec
[ 5] 109.00-110.00 sec 8.38 MBytes 70.3 Mbits/sec
[ 5] 110.00-111.00 sec 4.50 MBytes 37.7 Mbits/sec
[ 5] 111.00-112.00 sec 5.00 MBytes 41.9 Mbits/sec
^C[ 5] 112.00-113.00 sec 2.75 MBytes 23.2 Mbits/sec
This is the dmesg output, took just after the end of the test: dmesg
This is the logread (with verbose log enabled on wireless): logs
please ignore Kernel warnings, as I took logs and dmesg from a build on latest SNAPSHOT, but the issue is present even on 25.05.3 version, which does not report any kernel warning.
This is the wireless config:
config wifi-device 'radio0'
option type 'mac80211'
option path 'platform/soc/a000000.wifi'
option band '2g'
option channel '1'
option htmode 'HT40'
option noscan '1'
option country 'IT'
option country_ie '1'
list hostapd_options 'country3=0x49'
option cell_density '0'
option log_level '0'
config wifi-device 'radio1'
option type 'mac80211'
option path 'platform/soc/a800000.wifi'
option band '5g'
option channel 'auto'
option htmode 'VHT80'
option disabled '1'
option channels '36-48 100-140'
option country 'IT'
option country_ie '1'
list hostapd_options 'country3=0x49'
config wifi-iface 'main'
option device 'radio0'
option ssid 'ls-luka-net-3'
option ifname 'main'
option mode 'ap'
option encryption 'psk2'
option key '<omissis>'
option network 'lan'
option macfilter 'allow'
list maclist 'C0:A5:E8:6D:46:01'
I already tried the following on both OpenWRT versions tested, without results:
- Use a fixed 20Mhz channel width
- Use different wireless encryption, sae-mixed and psk2, not tried open network
- Set different channels
- Disable the SMPS on PC WiFi card (applied while performing the test above)
- Move the router to another location
- Turn off ALL home devices (switched off house main power) except the router (on UPS) and the PC (on battery)
- Change maximum transmit power
ABOUT SMPS: while investigating the issue, I noticed that with verbose wireless logging the router was reporting the following STA-OPMODE-SMPS-MODE-CHANGED messages, with:
- off: reported when switching to full throughput
- dynamic: reported when switching to low throughput
Wed Nov 27 15:37:00 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 off
Wed Nov 27 15:37:08 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 dynamic
Wed Nov 27 15:37:21 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 off
Wed Nov 27 15:37:29 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 dynamic
Wed Nov 27 15:37:42 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 off
Wed Nov 27 15:37:50 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 dynamic
Wed Nov 27 15:38:02 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 off
Wed Nov 27 15:38:11 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 dynamic
Wed Nov 27 15:38:24 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 off
Wed Nov 27 15:38:31 2024 daemon.notice hostapd: main: STA-OPMODE-SMPS-MODE-CHANGED c0:a5:e8:6d:46:01 dynamic
However, disabling SMPS on the PC wireless card just made messages disappear, without any change on the issue, so it seems to just be an effect and not a cause... Anyway it can be seen that messages are reported at regular intervals, with SMPS off for about 7 seconds, and SMPS dynamic for about 13 seconds (how weird...).
I also tried to sample the station dump (with only the PC connected ) with 1 second rate, reporting the latest SMPS-MODE-CHANGED value, with router moved at about 1.5m away from PC.
Maybe someone could notice something between station status changes:
station-dump-samples
Thanks to anyone able to read till there 
.