Netgear A6210 (MT7612U) speed

[dguerri]

Hello there, more a question than an issue (for now).

what speed should I expect from a Netgear A6210 (MT7612U) in 802.11s or IBSS mode using AC and 80Mhz channel?

I performed some tests in ideal conditions (i.e. no significant interferences and antennas few meters apart) and I got ~240Mbps at most.

This result (~200-240Mbps) is quite stable and reproducible, but I expected to get 866 Mbps (minus overhead, of course).

My configuration is:

• Channel 36, VHT80, 802.11s (and IBSS in a separate test), WPA3 (SAE), no mesh forwarding.
• The USB dongle is connected on a USB3 port of a Raspberry Pi 4.
• I have been using iperf3 with the IPv6 link local address, no additional routing protocol or traffic of any sort on the link.

Thanks!

[dguerri]

root@rpi4:~# iw dev mesh0 station dump
Station 44:a5:6e:xx:xx:xx (on mesh0)
    inactive time:  96 ms
    rx bytes:   291178641
    rx packets: 189919
    tx bytes:   11243913
    tx packets: 95357
    tx retries: 1957
    tx failed:  1
    rx drop misc:   6
    signal:     -32 [-32, -34] dBm
    signal avg: -31 [-31, -34] dBm
    Toffset:    102297998 us
    tx bitrate: 702.0 MBit/s VHT-MCS 8 80MHz VHT-NSS 2
    tx duration:    1428372 us
    rx bitrate: 780.0 MBit/s VHT-MCS 8 80MHz short GI VHT-NSS 2
    rx duration:    38491 us
    airtime weight: 256
    expected throughput:    362.90Mbps
    mesh llid:  0
    mesh plid:  0
    mesh plink: ESTAB
    mesh local PS mode: ACTIVE
    mesh peer PS mode:  ACTIVE
    mesh non-peer PS mode:  ACTIVE
    authorized: yes
    authenticated:  yes
    associated: yes
    preamble:   long
    WMM/WME:    yes
    MFP:        yes
    TDLS peer:  no
    DTIM period:    2
    beacon interval:100
    connected time: 84 seconds
    associated at [boottime]:   556.637s
    associated at:  1591699679203 ms
    current time:   1591699763221 ms

[dguerri]

FWIW, as it turned our channel 36 wasn't as free as I thought.

The maximum speed I could get was 348Mbps using WDS (AP + 1 STA no mesh) and moving to channel 149. For some reason I cannot use DFS channels.

Better, but still not what I was expecting.

Before starting a performance test:

During a performance test:

[ryderlee1110]

80Mhz VHT-MCS9 866 Mbps is just a theoretical value, and the actual date rate you can get is 866 Mbps * (0.7 ~0.8).

From what I saw - tx bitrate: 702.0 MBit/s VHT-MCS 8 80MHz VHT-NSS 2 rx bitrate: 780.0 MBit/s VHT-MCS 8 80MHz short GI VHT-NSS 2

The data didn't hit the ceiling - MCS 9 short GI. Rate adaptation is the determination of the optimal data transmission rate most appropriate for current wireless channel conditions.

[dguerri]

80Mhz VHT-MCS9 866 Mbps is just a theoretical value, and the actual date rate you can get is 866 Mbps * (0.7 ~0.8).

Yep, I was expecting something around that value.

The data didn't hit the ceiling - MCS 9 short GI. Rate adaptation is the determination of the optimal data transmission rate most appropriate for current wireless channel conditions.

That is very interesting. TIL, thanks. As it turned out the channel was busier than expected. I moved to 149, which is free (see my screenshots) and I am still surprised by the low rate. Keep in mind that radios were only ~1m apart.

What are the factors that can affect rate adaptation in my scenario?

[LorenzoBianconi]

80Mhz VHT-MCS9 866 Mbps is just a theoretical value, and the actual date rate you can get is 866 Mbps * (0.7 ~0.8).

Yep, I was expecting something around that value.

The data didn't hit the ceiling - MCS 9 short GI. Rate adaptation is the determination of the optimal data transmission rate most appropriate for current wireless channel conditions.

That is very interesting. TIL, thanks. As it turned out the channel was busier than expected. I moved to 149, which is free (see my screenshots) and I am still surprised by the low rate. Keep in mind that radios were only ~1m apart.

What are the factors that can affect rate adaptation in my scenario?

You can look at tx rate statistics in $cat /sys/kernel/debug/ieee80211/phyX/netdev:wlanY/stations/xx:yy:zz:aa:bb:cc/rc_stats

[dguerri]

FWIW, I can get to VHT-MCS 9 now that I moved to channel 149, although it's not stable:

Station 44:a5:6e:xx:xx:xx (on mesh0)
    inactive time:  1212 ms
    rx bytes:   36113921
    rx packets: 95034
    tx bytes:   1060521203
    tx packets: 346751
    tx retries: 7891
    tx failed:  1
    beacon loss:    1
    beacon rx:  2269
    rx drop misc:   0
    signal:     -40 [-40, -40] dBm
    signal avg: -40 [-40, -41] dBm
    beacon signal avg:  -40 dBm
    tx bitrate: 866.7 MBit/s VHT-MCS 9 80MHz short GI VHT-NSS 2
    tx duration:    11330313 us
    rx bitrate: 866.7 MBit/s VHT-MCS 9 80MHz short GI VHT-NSS 2
    rx duration:    784818 us
    airtime weight: 256
    expected throughput:    464.904Mbps
    authorized: yes
    authenticated:  yes
    associated: yes
    preamble:   long
    WMM/WME:    yes
    MFP:        yes
    TDLS peer:  no
    DTIM period:    2
    beacon interval:100
    short slot time:yes
    connected time: 257 seconds
    associated at [boottime]:   27.990s
    associated at:  1591821656819 ms
    current time:   1591821910363 ms

These are the stats from debugfs, but I will have to do some research before I can read it correctly :)

root@hallway:~# cat /sys/kernel/debug/ieee80211/phy0/netdev:mesh0/stations/44\:a5\:6e\:xx\:xx\:xx/rc_stats

              best   ____________rate__________    ____statistics___    _____last____    ______sum-of________
mode guard #  rate  [name   idx airtime  max_tp]  [avg(tp) avg(prob)]  [retry|suc|att]  [#success | #attempts]
VHT20 LGI 1         MCS0/1  170    1477     4.8       4.8      86.1       3     0 0            19   22
VHT20 LGI 1         MCS1/1  171     738     9.7       0.0       0.0       0     0 0             0   0
VHT20 LGI 1         MCS2/1  172     492    17.0      17.0     100.0       0     0 0             1   1
VHT20 LGI 1         MCS3/1  173     369    21.9       0.0       0.0       0     0 0             0   0
VHT20 LGI 1         MCS4/1  174     246    34.1       0.0       0.0       0     0 0             0   0
VHT20 LGI 1         MCS5/1  175     185    46.3       0.0       0.0       0     0 0             0   0
VHT20 LGI 1         MCS6/1  176     164    51.2       0.0       0.0       0     0 0             0   0
VHT20 LGI 1         MCS7/1  177     148    58.5       0.0       0.0       0     0 0             0   0
VHT20 LGI 1         MCS8/1  178     123    68.3       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS0/2  180     738     9.7       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS1/2  181     369    21.9       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS2/2  182     246    34.1      34.1     100.0       0     0 0             1   1
VHT20 LGI 2         MCS3/2  183     185    46.3       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS4/2  184     123    68.3       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS5/2  185      92    90.3       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS6/2  186      82   102.5       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS7/2  187      74   112.3       0.0       0.0       0     0 0             0   0
VHT20 LGI 2         MCS8/2  188      62   134.2     134.2     100.0       0     0 0             1   1
VHT20 SGI 1         MCS0/1  210    1329     4.8       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS1/1  211     665    12.2       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS2/1  212     443    19.5      19.5     100.0       0     0 0             1   1
VHT20 SGI 1         MCS3/1  213     332    24.4       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS4/1  214     222    39.0       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS5/1  215     166    51.2       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS6/1  216     148    58.5       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS7/1  217     133    63.4       0.0       0.0       0     0 0             0   0
VHT20 SGI 1         MCS8/1  218     111    75.6       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS0/2  220     665    12.2       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS1/2  221     332    24.4       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS2/2  222     222    39.0      39.0     100.0       3     0 0            72   72
VHT20 SGI 2         MCS3/2  223     166    51.2       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS4/2  224     111    75.6       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS5/2  225      83   100.0       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS6/2  226      74   112.3       0.0       0.0       0     0 0             0   0
VHT20 SGI 2         MCS7/2  227      67   124.5     124.5     100.0       0     0 0             2   2
VHT20 SGI 2         MCS8/2  228      56   148.9     148.9      96.4       0     0 0             3   4
VHT40 LGI 1         MCS0/1  250     711    12.2       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS1/1  251     356    24.4       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS2/1  252     237    36.6      36.6     100.0       0     0 0             1   1
VHT40 LGI 1         MCS3/1  253     178    48.8       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS4/1  254     119    70.8       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS5/1  255      89    95.2       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS6/1  256      79   104.9       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS7/1  257      71   117.1       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS8/1  258      59   139.1       0.0       0.0       0     0 0             0   0
VHT40 LGI 1         MCS9/1  259      53   153.8     153.8     100.0       0     0 0             1   1
VHT40 LGI 2         MCS0/2  260     356    24.4       0.0       0.0       0     0 0             0   0
VHT40 LGI 2         MCS1/2  261     178    48.8       0.0       0.0       0     0 0             0   0
VHT40 LGI 2         MCS2/2  262     119    70.8      70.8     100.0       3     0 0            57   57
VHT40 LGI 2         MCS3/2  263      89    95.2       0.0       0.0       0     0 0             0   0
VHT40 LGI 2         MCS4/2  264      59   139.1       0.0       0.0       0     0 0             0   0
VHT40 LGI 2         MCS5/2  265      44   180.6     180.6     100.0       0     0 0            11   11
VHT40 LGI 2         MCS6/2  266      40   200.1     200.1     100.0       0     0 0            11   11
VHT40 LGI 2         MCS7/2  267      36   222.1     222.1      90.5       0     0 0            46   68
VHT40 LGI 2         MCS8/2  268      30   261.2      46.3      16.4       0     0 0           165   233
VHT40 LGI 2         MCS9/2  269      27   285.6     278.3      87.9       3     0 0           481   711
VHT40 SGI 1         MCS0/1  290     640    12.2       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS1/1  291     320    26.8       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS2/1  292     214    39.0      39.0     100.0       0     0 0             1   1
VHT40 SGI 1         MCS3/1  293     160    53.7       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS4/1  294     107    80.5       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS5/1  295      80   104.9       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS6/1  296      71   117.1       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS7/1  297      64   129.3       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS8/1  298      54   153.8       0.0       0.0       0     0 0             0   0
VHT40 SGI 1         MCS9/1  299      48   168.4     168.4     100.0       0     0 0             1   1
VHT40 SGI 2         MCS0/2  300     320    26.8       0.0       0.0       0     0 0             0   0
VHT40 SGI 2         MCS1/2  301     160    53.7       0.0       0.0       0     0 0             0   0
VHT40 SGI 2         MCS2/2  302     107    80.5      80.5     100.0       3     0 0            82   82
VHT40 SGI 2         MCS3/2  303      80   104.9     104.9      94.0       0     0 0            22   23
VHT40 SGI 2         MCS4/2  304      54   153.8      24.4      14.3       0     0 0            11   31
VHT40 SGI 2         MCS5/2  305      40   200.1     131.8      59.6       0     0 0            21   52
VHT40 SGI 2         MCS6/2  306      36   219.7      92.7      37.7       3     0 0            44   85
VHT40 SGI 2         MCS7/2  307      32   241.6      39.0      14.5       0     0 0            43   107
VHT40 SGI 2         MCS8/2  308      27   283.2      80.5      25.9       0     0 0           139   246
VHT40 SGI 2         MCS9/2  309      24   310.0     307.6      88.7       3     0 0           496   724
VHT80 LGI 1         MCS0/1  330     328    26.8       0.0       0.0       0     0 0             0   0
VHT80 LGI 1         MCS1/1  331     164    51.2      51.2     100.0       0     0 0             1   1
VHT80 LGI 1         MCS2/1  332     109    78.1       0.0       0.0       0     0 0             0   1
VHT80 LGI 1         MCS3/1  333      82   102.5     102.5      90.8       0     0 0            10   11
VHT80 LGI 1         MCS4/1  334      55   151.3     151.3     100.0       0     0 0            31   31
VHT80 LGI 1         MCS5/1  335      41   195.3       0.0       0.0       0     0 0             0   11
VHT80 LGI 1         MCS6/1  336      36   217.2     217.2      93.9       3     0 0           110   121
VHT80 LGI 1         MCS7/1  337      33   236.8     148.9      56.2       0     0 0            31   61
VHT80 LGI 1         MCS8/1  338      27   278.3     278.3     100.0       3     0 0            67   127
VHT80 LGI 1         MCS9/1  339      25   305.1     202.6      60.2       3     0 0           294   418
VHT80 LGI 2         MCS0/2  340     164    51.2      43.9      76.9       0     0 0            10   13
VHT80 LGI 2         MCS1/2  341      82   102.5      95.2      83.3       0     0 0            10   12
VHT80 LGI 2         MCS2/2  342      55   151.3     151.3     100.0       0     0 0            53   53
VHT80 LGI 2         MCS3/2  343      41   195.3     195.3     100.0       0     0 0           136   145
VHT80 LGI 2         MCS4/2  344      28   278.3     278.3     100.0       0     0 0           336   450
VHT80 LGI 2         MCS5/2  345      21   351.5     139.1      35.5       3     0 0           550   863
VHT80 LGI 2         MCS6/2  346      18   390.6     178.2      40.9       3     0 0          1320   2086
VHT80 LGI 2   B     MCS7/2  347      17   422.3     422.3     100.0       3     0 0          6649   8067
VHT80 LGI 2         MCS8/2  348      14   485.8     390.6      72.3       3     0 0         13330   17173
VHT80 LGI 2         MCS9/2  349      13   522.4     300.2      51.9       3     0 0          3586   4891
VHT80 SGI 1         MCS0/1  370     295    29.2       0.0       0.0       0     0 0             0   0
VHT80 SGI 1         MCS1/1  371     148    58.5       0.0       0.0       0     0 0             0   0
VHT80 SGI 1         MCS2/1  372      99    85.4      85.4     100.0       0     0 0             1   1
VHT80 SGI 1         MCS3/1  373      74   112.3       0.0       0.0       0     0 0             0   0
VHT80 SGI 1         MCS4/1  374      49   166.0     166.0     100.0       0     0 0            30   30
VHT80 SGI 1         MCS5/1  375      37   214.8     214.8     100.0       0     0 0            63   63
VHT80 SGI 1         MCS6/1  376      33   239.2     197.7      74.9       0     0 0            32   95
VHT80 SGI 1         MCS7/1  377      30   261.2     187.9      65.2       3     0 0           236   360
VHT80 SGI 1         MCS8/1  378      25   302.7     214.8      63.5       3     0 0           315   616
VHT80 SGI 1      P  MCS9/1  379      22   332.0     292.9      79.5       3     0 0           297   608
VHT80 SGI 2         MCS0/2  380     148    58.5      53.7      85.6       0     0 0            61   67
VHT80 SGI 2         MCS1/2  381      74   112.3     102.5      82.3       0     0 0           114   126
VHT80 SGI 2         MCS2/2  382      49   166.0     166.0      91.2       3     0 0           271   277
VHT80 SGI 2         MCS3/2  383      37   214.8     214.8      95.4       0     0 0           376   504
VHT80 SGI 2         MCS4/2  384      25   302.7     302.7     100.0       3     0 0          1359   1686
VHT80 SGI 2         MCS5/2  385      19   383.3     200.1      47.2       3     0 0          3035   3984
VHT80 SGI 2         MCS6/2  386      16   424.8     339.3      72.2       3     0 0          7652   9467
VHT80 SGI 2  A      MCS7/2  387      15   458.9     458.9      99.8       3   224 224       30158   33953
VHT80 SGI 2    C    MCS8/2  388      12   524.9     410.1      70.4       3     0 0         36130   43416
VHT80 SGI 2     D   MCS9/2  389      11   561.5     405.2      64.8       3     0 0         55352   64211

Total packet count::    ideal 441616      lookaround 81
Average # of aggregated frames per A-MPDU: 23.3

[dguerri]

A video with live stats: https://youtu.be/LCF49q1seQw

[dguerri]

The "M" shaped signal on channels 52 - 64 is super-interesting... It always starts when I start heavy transfers on channel 149...