QCA9880 slow performance adhoc/IBSS mode

Ben Greear greearb at candelatech.com
Wed Mar 1 06:50:13 PST 2017



On 03/01/2017 12:21 AM, Ralph Houthoofdt wrote:
> Dear Ben,
>
> Indeed, if I try AP/STA mode I get better bitrates and speeds (this is with
> VHT40)
> RX: 400.0 Mbit/s, 40MHz, VHT-MCS 9, VHT-NSS 2, Short GI
> TX: 300.0 Mbit/s, 40MHz, VHT-MCS 7, VHT-NSS 2, Short GI
>
> I only have 4 antennas installed on my APUs, so I'm only using 2 spatial
> streams max.
> These speeds seem ok.
>
> It just seems strange that on adhoc I only get either RX or TX to have good
> rates.
>
> Thanks for your help!

If you have only two antenna connected, make sure it is chain 0 and 1,
and then use 'iw' to set the tx chain mask to 0x3.  That way, the NIC will
not waste time trying to use the 3-NSS rates.

Maybe too running at VHT40 helps somehow?

Thanks,
Ben

>
> Met vriendelijke groeten,
> Ralph Houthoofdt
> Student industriële wetenschappen informatica
>
> -----Original Message-----
> From: Ben Greear [mailto:greearb at candelatech.com]
> Sent: dinsdag 28 februari 2017 23:03
> To: Ralph Houthoofdt <ralph.houthoofdt at ugent.be>
> Cc: ath10k at lists.infradead.org
> Subject: Re: QCA9880 slow performance adhoc/IBSS mode
>
> I've pushed 475+Mbps on apu2 over wifi, maybe more.  That was AP mode, most
> likely.
>
> IBSS on ath10k cannot do AMSDU, so you loose a bit of performance there, but
> otherwise it should be pretty similar to AP/STA mode.  To verify, try
> running in AP/STA mode.
>
> Thanks,
> Ben
>
> On 02/28/2017 01:48 PM, Ralph Houthoofdt wrote:
>> Dear Ben,
>>
>> The speeds I'm reporting are UDP using these commands for the client:
>> Iperf3 -uVc <serverAddress> -b0 -w128k
>> Iperf3 -uRVc <serverAddress> -b0 -w128k
>>
>> I will try relocating the nodes and try different antenna positions
>> and angles.
>> As you see it, this problem is purely because of the environment, not
>> because of the configuration or drivers?
>>
>> I will let you know what the results of relocation are tomorrow.
>> Thanks for your help!
>>
>> Kind regards,
>> Met vriendelijke groeten,
>> Ralph Houthoofdt
>> Student master industriële wetenschappen: informatica
>>
>> -----Original Message-----
>> From: Ben Greear [mailto:greearb at candelatech.com]
>> Sent: dinsdag 28 februari 2017 19:12
>> To: Ralph Houthoofdt <ralph.houthoofdt at ugent.be>
>> Cc: ath10k at lists.infradead.org
>> Subject: Re: QCA9880 slow performance adhoc/IBSS mode
>>
>> You try UDP yet, or is this all TCP?
>>
>> Also, with some better antenna positions and/or better other RF
>> environment, you should see NSS of 3, hopefully MCS of 6 or higher.
>>
>> On 02/28/2017 10:02 AM, Ralph Houthoofdt wrote:
>>> Dear Ben,
>>>
>>> I ran the same test again, this time running the iperf3 server on my
>>> laptop and the client on the node. I could indeed see CPU usage rise
>>> to 40% on my laptop, the node stayed at roughly 10%. The speeds
>>> remained roughly the same. 215Mbit one way, 40Mbit the other.
>>>
>>> As for the tx/rx rates I get these values:
>>> tx bitrate:     234.0 MBit/s VHT-MCS 3 80MHz VHT-NSS 2
>>> rx bitrate:     87.8 MBit/s VHT-MCS 2 80MHz VHT-NSS 1
>>>
>>> I set the 4 antennas facing different directions approximately at 135
>>> degree angles relative to the device.
>>
>> You try UDP yet, or is this all TCP?
>>
>> Also, with some better antenna positions and/or better other RF
>> environment, you should see NSS of 3, hopefully MCS of 6 or higher.
>>
>> The 9880 has 3 antenna, so how did you get to 4?
>>
>> Thanks,
>> Ben
>>
>>>
>>> Thank you for your help so far. I will be leaving home for a few
>>> hours and will be responding to any replies tomorrow morning.
>>>
>>> Met vriendelijke groeten,
>>> Ralph Houthoofdt
>>> Student industriële wetenschappen informatica
>>>
>>> -----Original Message-----
>>> From: Ben Greear [mailto:greearb at candelatech.com]
>>> Sent: dinsdag 28 februari 2017 18:42
>>> To: Ralph Houthoofdt <ralph.houthoofdt at ugent.be>
>>> Cc: ath10k at lists.infradead.org
>>> Subject: Re: QCA9880 slow performance adhoc/IBSS mode
>>>
>>> Try UDP to make sure you are not hitting a TCP issue.
>>>
>>> Try running iperf server on another laptop so that CPU of your nodes
>>> is less important.
>>>
>>> Check the tx/rx encoding rates to make sure you are getting good RF
>>> behaviour.  'iw ... station dump'
>>>
>>> Ensure antennas are not pointing all in the same direction so that
>>> you can get some diversity working.
>>>
>>> Thanks,
>>> Ben
>>>
>>> On 02/28/2017 09:36 AM, Ralph Houthoofdt wrote:
>>>> Dear Ben,
>>>>
>>>> Thank you for your quick reply.
>>>>
>>>> My mesh is running on channel 36  using VHT80 and a TX power of 20
>>>> dbm, the maximum allowed according to my regulatory settings from iw
>>>> reg get. The hwmode is set as 11a.
>>>> I have also enable the following ht_capabilities on my radio in
>>>> /etc/config/wireless:
>>>>
>>>>         list ht_capab 'short_gi_80'
>>>>         list ht_capab 'max-mpdu-11454'
>>>>         list ht_capab 'TX-STBC-2BY1'
>>>>         list ht_capab 'RX-STBC1'
>>>>         list ht_capab 'RX-ANTENNA-PATTERN'
>>>>         list ht_capab 'TX-ANTENNA-PATTERN'
>>>>         list ht_capab 'MAX-A-MPDU-LEN-EXP7'
>>>>
>>>> I just finished running iperf3 from my laptop (2nd gen Core i7) to
>>>> one of my nodes. The results were indeed a bit different.
>>>> Iperf server was running on my node and my laptop was the client.
>>>> UDP:
>>>> Normal: average result of 221Mbit, which is pretty normal I think.
>>>> Reverse: average result of 41Mbit, which is better than the average
>>>> 20Mbit I got when running iperf3 using 2 nodes.
>>>> TCP:
>>>> Normal: average result of 49Mbit
>>>> Reverse: average result of 35.4Mbit
>>>>
>>>> In terms of congestion, I'm not sure what you mean, but I'm in a low
>>>> populated area with few wireless access points. I disabled all my
>>>> 5GHz devices except for the mesh nodes. InSSIDer only shows my nodes
>>>> in the 5GHz range.
>>>>
>>>> Is there anything else I could try for you?
>>>>
>>>> Met vriendelijke groeten,
>>>> Ralph Houthoofdt
>>>> Student industriële wetenschappen informatica
>>>>
>>>> -----Original Message-----
>>>> From: ath10k [mailto:ath10k-bounces at lists.infradead.org] On Behalf
>>>> Of Ben Greear
>>>> Sent: dinsdag 28 februari 2017 17:56
>>>> To: Ralph Houthoofdt <ralph at rora.be>; ath10k at lists.infradead.org
>>>> Subject: Re: QCA9880 slow performance adhoc/IBSS mode
>>>>
>>>> Run iperf on a separate machine, as the apu2 have too weak of a CPU
>>>> to drive the wifi network at full speed.  And, publish what results
>>>> you do get, including RF information such as channel and how
>>>> congested is your test area.  Try udp as well as tcp.
>>>>
>>>> Thanks,
>>>> Ben
>>>>
>>>> On 02/28/2017 08:51 AM, Ralph Houthoofdt wrote:
>>>>> Dear all,
>>>>>
>>>>> I’m currently doing me masters thesis on the subject of Wireless
>>>>> Mesh Networks and how to optimize them for home use.
>>>>> The devices I use are 5x PC Engine APU2c4 with 2x QCA9880 chip
>>>>> (Compex WLE900VX). All of them are running LEDE (OpenWRT fork).
>>>>>
>>>>> The problem I’m experiencing is the same as
>>>>> http://lists.infradead.org/pipermail/ath10k/2017-January/009075.html .
>>>>> Using the tips mentioned I did not come to a better performance.
>>>>> I’m thinking it’s driver related..
>>>>> When running iperf3 only one direction is running at a reasonable
>>>>> throughput. Since I am using adhoc mode primarily I decided to use
>>>>> these
>>>>> packages:
>>>>> -	Kmod-ath10k-ct
>>>>> -	Ath10k-firmware-qca988x-ct
>>>>> Some sources on the internet said that using the Candela Tech
>>>>> drivers should result in better support for adhoc/mesh networks.
>>>>>
>>>>> As suggested in the other issue linked above, I switched TCP
>>>>> congestion control to ‘Reno’ instead of the default ‘Cubic’.
>>>>> I also did try the command “iw reg set BE” since I am from Belgium,
>>>>> but running “iw reg get” right after still gave me US as a result.
>>>>>
>>>>> Let me know what additional command info I should post. Any help
>>>>> would be greatly appreciated.
>>>>>
>>>>> Iwconfig:
>>>>> adhoc0    IEEE 802.11  ESSID:"mesh"
>>>>>           Mode:Ad-Hoc  Frequency:5.18 GHz  Cell: 02:CA:FE:CA:CA:40
>>>>>           Tx-Power=20 dBm
>>>>>           RTS thr:off   Fragment thr:off
>>>>>           Encryption key:off
>>>>>           Power Management:off
>>>>>
>>>>>
>>>>> Iw reg get (I’m from Belgium):
>>>>> global
>>>>> country BE: DFS-ETSI
>>>>>         (2402 - 2482 @ 40), (N/A, 20), (N/A)
>>>>>         (5170 - 5250 @ 80), (N/A, 20), (N/A), AUTO-BW
>>>>>         (5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS, AUTO-BW
>>>>>         (5490 - 5710 @ 160), (N/A, 27), (0 ms), DFS
>>>>>         (57000 - 66000 @ 2160), (N/A, 40), (N/A)
>>>>>
>>>>> phy#1
>>>>> country US: DFS-FCC
>>>>>         (2402 - 2472 @ 40), (N/A, 30), (N/A)
>>>>>         (5170 - 5250 @ 80), (N/A, 23), (N/A), AUTO-BW
>>>>>         (5250 - 5330 @ 80), (N/A, 23), (0 ms), DFS, AUTO-BW
>>>>>         (5490 - 5730 @ 160), (N/A, 23), (0 ms), DFS
>>>>>         (5735 - 5835 @ 80), (N/A, 30), (N/A)
>>>>>         (57240 - 63720 @ 2160), (N/A, 40), (N/A)
>>>>>
>>>>> phy#0
>>>>> country US: DFS-FCC
>>>>>         (2402 - 2472 @ 40), (N/A, 30), (N/A)
>>>>>         (5170 - 5250 @ 80), (N/A, 23), (N/A), AUTO-BW
>>>>>         (5250 - 5330 @ 80), (N/A, 23), (0 ms), DFS, AUTO-BW
>>>>>         (5490 - 5730 @ 160), (N/A, 23), (0 ms), DFS
>>>>>         (5735 - 5835 @ 80), (N/A, 30), (N/A)
>>>>>         (57240 - 63720 @ 2160), (N/A, 40), (N/A)
>>>>>
>>>>>
>>>>> Kind regards,
>>>>> Met vriendelijke groeten,
>>>>> Ralph Houthoofdt
>>>>> Student industriële wetenschappen informatica
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> ath10k mailing list
>>>>> ath10k at lists.infradead.org
>>>>> http://lists.infradead.org/mailman/listinfo/ath10k
>>>>>
>>>>
>>>> --
>>>> Ben Greear <greearb at candelatech.com> Candela Technologies Inc
>>>> http://www.candelatech.com
>>>>
>>>> _______________________________________________
>>>> ath10k mailing list
>>>> ath10k at lists.infradead.org
>>>> http://lists.infradead.org/mailman/listinfo/ath10k
>>>>
>>>
>>> --
>>> Ben Greear <greearb at candelatech.com>
>>> Candela Technologies Inc  http://www.candelatech.com
>>>
>>
>> --
>> Ben Greear <greearb at candelatech.com>
>> Candela Technologies Inc  http://www.candelatech.com
>>
>
> --
> Ben Greear <greearb at candelatech.com>
> Candela Technologies Inc  http://www.candelatech.com
>

-- 
Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com



More information about the ath10k mailing list