On 19-9-2016 8:36, Jörg Krause wrote:
> Hi Arend,
>
> On Wed, 2016-09-14 at 20:13 +0200, Arend Van Spriel wrote:
>> On 14-9-2016 15:41, Jörg Krause wrote:
>>>
>>> Hi,
>>>
>>> On Mon, 2016-08-29 at 23:15 +0200, Jörg Krause wrote:
>>>>
>>>> On Mi, 2016-08-24 at 20:35 +0200, Arend Van Spriel wrote:
>>>>>
>>>>>
>>>>> On 22-8-2016 15:37, Jörg Krause wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>> Hi all,
>>>>>>
>>>>>> I am back from vacation and I'd like to do more
>>>>>> investigations
>>>>>> about
>>>>>> this issue. Please see my comments below...
>>>>>>
>>>>>> On Sun, 2016-08-07 at 13:41 +0200, Arend van Spriel wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On 06-08-16 16:12, Jörg Krause wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Hi all,
>>>>>>>
>>>>>>> A bit weird email format making it a bit hard to determine
>>>>>>> where
>>>>>>> your
>>>>>>> last reply starts...
>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> On Fr, 2016-08-05 at 17:56 -0700, Franky Lin wrote:
>>>>>>>>
>>>>>>>> On Fri, Aug 5, 2016 at 2:29 PM, Jörg Krause <joerg.krause
>>>>>>>> @emb
>>>>>>>> ed
>>>>>>>> ded.
>>>>>>>> ro
>>>>>>>> cks>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Am 5. August 2016 23:01:10 MESZ, schrieb Arend Van Spriel
>>>>>>>> <
>>>>>>>> arend.vanspriel@xxxxxxxxxxxx>:
>>>>>>>>
>>>>>>>>
>>>>>>>> Op 5 aug. 2016 22:46 schreef "Jörg Krause"
>>>>>>>> <joerg.krause@embedded.rocks>:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> I'm using a custom ARM board with an BCM43362 wifi chip
>>>>>>>> from
>>>>>>>>
>>>>>>>> Broadcom.
>>>>>>>>
>>>>>>>>
>>>>>>>> The wifi chip is attached via SDIO to the controller with
>>>>>>>> a
>>>>>>>> clock of
>>>>>>>> 48MHz. Linux kernel version is 4.7.
>>>>>>>>
>>>>>>>> When measuring the network bandwidth with iperf3 I get a
>>>>>>>> bandwith of
>>>>>>>> only around 5 Mbps. I found a similar thread at the
>>>>>>>> Broadcom
>>>>>>>>
>>>>>>>> community
>>>>>>>>
>>>>>>>>
>>>>>>>> [1] where the test was done with a M4 CPU + BCM43362 and
>>>>>>>> an
>>>>>>>> average
>>>>>>>> result of 3.3 Mbps.
>>>>>>>>
>>>>>>>> Interestingly, a BCM43362 Wi-Fi Dev Kit [2] notes a TCP
>>>>>>>> data
>>>>>>>>
>>>>>>>> throughput
>>>>>>>>
>>>>>>>>
>>>>>>>> greater than 20 Mbps.
>>>>>>>>
>>>>>>>> Why is the throughput I measured much lower? Note that I
>>>>>>>> measured
>>>>>>>> several times with almost no neighbor devices or
>>>>>>>> networks.
>>>>>>>>
>>>>>>>> This is a test sample measured with iperf3:
>>>>>>>>
>>>>>>>> $ iperf3 -c 192.168.2.1 -i 1 -t 10
>>>>>>>> Connecting to host 192.168.2.1, port 5201
>>>>>>>> [ 4] local 192.168.2.155 port 36442 connected to
>>>>>>>> 192.168.2.1
>>>>>>>>
>>>>>>>> port
>>>>>>>>
>>>>>>>>
>>>>>>>> 5201
>>>>>>>> [ ID]
>>>>>>>> Interval Transfer Bandwidth Retr Cwn
>>>>>>>> d
>>>>>>>> [ 4] 0.00-1.00 sec 615 KBytes 5.04
>>>>>>>> Mbits/sec 0 56.6
>>>>>>>> KBytes
>>>>>>>> [ 4] 1.00-2.00 sec 622 KBytes 5.10
>>>>>>>> Mbits/sec 0 84.8
>>>>>>>> KBytes
>>>>>>>> [ 4] 2.00-3.00 sec 625 KBytes 5.12
>>>>>>>> Mbits/sec 0 113
>>>>>>>> KBytes
>>>>>>>> [ 4] 3.00-4.00 sec 571 KBytes 4.68
>>>>>>>> Mbits/sec 0 140
>>>>>>>> KBytes
>>>>>>>> [ 4] 4.00-5.00 sec 594 KBytes 4.87
>>>>>>>> Mbits/sec 0 167
>>>>>>>> KBytes
>>>>>>>> [ 4] 5.00-6.00 sec 628 KBytes 5.14
>>>>>>>> Mbits/sec 0 195
>>>>>>>> KBytes
>>>>>>>> [ 4] 6.00-7.00 sec 619 KBytes 5.07
>>>>>>>> Mbits/sec 0 202
>>>>>>>> KBytes
>>>>>>>> [ 4] 7.00-8.00 sec 608 KBytes 4.98
>>>>>>>> Mbits/sec 0 202
>>>>>>>> KBytes
>>>>>>>> [ 4] 8.00-9.00 sec 602 KBytes 4.93
>>>>>>>> Mbits/sec 0 202
>>>>>>>> KBytes
>>>>>>>> [ 4] 9.00-10.00 sec 537 KBytes 4.40
>>>>>>>> Mbits/sec 0 202
>>>>>>>> KBytes
>>>>>>>> - - - - - - - - - - - - - - - - - - - - - - - - -
>>>>>>>> [ ID]
>>>>>>>> Interval Transfer Bandwidth Retr
>>>>>>>> [ 4] 0.00-10.00 sec 5.88 MBytes 4.93
>>>>>>>> Mbits/sec 0 sender
>>>>>>>> [ 4] 0.00-10.00 sec 5.68 MBytes 4.76
>>>>>>>> Mbits/sec receiver
>>>>>>>>
>>>>>>>>
>>>>>>>> Not overly familiar with iperf3. Do these lines mean you
>>>>>>>> are
>>>>>>>> doing
>>>>>>>> bidirectional test, ie. upstream and downstream at the
>>>>>>>> same
>>>>>>>> time.
>>>>>>>> Another
>>>>>>>> thing affecting tput could be power-save.
>>>>>>>>
>>>>>>>>
>>>>>>>> No, iperf3 does not support bidrectional test. Power-save
>>>>>>>> is
>>>>>>>> turned
>>>>>>>> off.
>>>>>>>>
>>>>>>>> What does iw link say?
>>>>>>>>
>>>>>>>
>>>>>>> but I guess it starts here!
>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> I compared the results with a Cubietruck I have:
>>>>>>>>
>>>>>>>> # iperf3 -s
>>>>>>>> -------------------------------------------------------
>>>>>>>> ----
>>>>>>>> Server listening on 5201
>>>>>>>> -------------------------------------------------------
>>>>>>>> ----
>>>>>>>> Accepted connection from 192.168.178.46, port 42906
>>>>>>>> [ 5] local 192.168.178.38 port 5201 connected to
>>>>>>>> 192.168.178.46
>>>>>>>> port
>>>>>>>> 42908
>>>>>>>> [ ID] Interval Transfer Bandwidth
>>>>>>>> [ 5] 0.00-1.00 sec 2.29 MBytes 19.2
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 1.00-2.00 sec 2.21 MBytes 18.5
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 2.00-3.00 sec 2.17 MBytes 18.2
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 3.00-4.00 sec 2.09 MBytes 17.6
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 4.00-5.00 sec 2.20 MBytes 18.5
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 5.00-6.00 sec 2.64 MBytes 22.1
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 6.00-7.00 sec 2.67 MBytes 22.4
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 7.00-8.00 sec 2.62 MBytes 22.0
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 8.00-9.00 sec 2.35 MBytes 19.8
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 9.00-10.00 sec 2.30 MBytes 19.3
>>>>>>>> Mbits/sec
>>>>>>>> [ 5] 10.00-10.03 sec 83.4 KBytes 23.5
>>>>>>>> Mbits/sec
>>>>>>>> - - - - - - - - - - - - - - - - - - - - - - - - -
>>>>>>>> [ ID]
>>>>>>>> Interval Transfer Bandwidth Retr
>>>>>>>> [ 5] 0.00-10.03 sec 23.9 MBytes 20.0
>>>>>>>> Mbits/sec 0 sender
>>>>>>>> [ 5] 0.00-10.03 sec 23.6 MBytes 19.8
>>>>>>>> Mbits/sec receiver
>>>>>>>>
>>>>>>>> # iw dev wlan0 link
>>>>>>>> Connected to xx:xx:xx:xx:xx (on wlan0)
>>>>>>>> SSID: xxx
>>>>>>>> freq: 2437
>>>>>>>> tx bitrate: 65.0 MBit/s
>>>>>>>>
>>>>>>>> bss flags: short-preamble short-slot-time
>>>>>>>> dtim period: 1
>>>>>>>> beacon int: 100
>>>>>>>
>>>>>>> Too bad RSSI is not in the output above. That may be due to
>>>>>>> a
>>>>>>> regression
>>>>>>> in our driver which has been fixed by commit 94abd778a7bb
>>>>>>> ("brcmfmac:
>>>>>>> add fallback for devices that do not report per-chain
>>>>>>> values").
>>>>>>> However,
>>>>>>> the tx bitrate seems within the same range as the other
>>>>>>> platform.
>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> The Cubietruck works also with the brcmfmac driver.
>>>>>>>>
>>>>>>>> May it depend on the NVRAM file?
>>>>>>>
>>>>>>> Not sure. Can you tell me a bit more about the custom ARM
>>>>>>> board.
>>>>>>> Does
>>>>>>> it
>>>>>>> use the same wifi module as Cubietruck, ie. the AMPAK
>>>>>>> AP6210?
>>>>>>> If
>>>>>>> you
>>>>>>> can
>>>>>>> make a wireshark sniff we can check the actual bitrate and
>>>>>>> medium
>>>>>>> density in terms of packets. Another thing to look at is
>>>>>>> the
>>>>>>> SDIO
>>>>>>> host
>>>>>>> controller. In brcmf_sdiod_sgtable_alloc() some key values
>>>>>>> are
>>>>>>> used
>>>>>>> from
>>>>>>> the host controller. It only logs the number of entries of
>>>>>>> the
>>>>>>> scatter-gather table, but could you add the other values in
>>>>>>> this
>>>>>>> function that are used to determine the number of entries.
>>>>>>
>>>>>> My board uses the BCM43362 chip solely (no Bluetooth)
>>>>>> attached to
>>>>>> the
>>>>>> SDIO interface of a NXP i.MX28 processor.
>>>>>>
>>>>>> I added some additional printk() to
>>>>>> brcmf_sdiod_sgtable_alloc().
>>>>>> These
>>>>>> are the values printed after modprobe brcmfmac:
>>>>>>
>>>>>> [ 8.926657] sg_support=1
>>>>>> [ 8.929440] max_blocks=511
>>>>>> [ 8.932213] max_request_size=261632
>>>>>> [ 8.935741] max_segment_count=52
>>>>>> [ 8.939005] max_segment_size=65280
>>>>>> [ 8.946095] nents=35
>>>>>
>>>>> Thanks. That looks good.
>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> Additionally I attached a xz compresses wireshark sniff while
>>>>>> running
>>>>>> iper3 between the BCM43362 running as in AP mode with iperf3
>>>>>> as a
>>>>>> server and a PC in station mode running iperf3 as a client.
>>>>>
>>>>> Looking at the sniff it seems you captured on the ethernet
>>>>> side.
>>>>> That
>>>>> does not give me any 802.11 specific info. Can you make a
>>>>> wireless
>>>>> capture preferably without encryption.
>>>>
>>>> You,re right! Sorry for this mistake. I did a re-capture on the
>>>> wireless side now.
>>>
>>> Anything new about this? Anything I can do to help?
>>
>> I missed your previous email. Was already wondering whether to ping
>> you.
>> Digging around in my email folders I found it so will take a look at
>> it.
>
> Did you had some time to look at this?
Ehm. I still only see TCP stuff. To capture 802.11 management frames you
need preferably a dedicated device using monitor mode [1].
Regards,
Arend
[1]
https://wireless.wiki.kernel.org/en/users/documentation/modes#monitor_mode
