LinuxLists.cc - TCP data throughput for BCM43362

2016-08-05 20:57:28

Subject: TCP data throughput for BCM43362

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  Cwnd
[  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

[1] https://community.broadcom.com/thread/3978
[2] http://www.mouser.de/new/broadcom/broadcom-bcm943362wcd4/

Best regards
Jörg Krause

2016-08-05 21:29:50

by Jörg Krause

[permalink] [raw]

Subject: Re: TCP data throughput for BCM43362

Am 5. August 2016 23:01:10 MESZ, schrieb Arend Van Spriel <[email protected]>:
>Op 5 aug. 2016 22:46 schreef "Jörg Krause"
><[email protected]>:
>>
>> 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 Cwnd
>> [ 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.

2016-09-21 14:15:57

by Arend Van Spriel

[permalink] [raw]

Subject: Re: TCP data throughput for BCM43362

On 19-09-16 08:36, 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
>>>>>>>> <
>>>>>>>> [email protected]>:
>>>>>>>>
>>>>>>>>
>>>>>>>> Op 5 aug. 2016 22:46 schreef "Jörg Krause"
>>>>>>>> <[email protected]>:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> 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?

Sorry for the delay, but I am kinda swamped. Will try spent some time on
it later this week.

Regards,
Arend

2016-09-22 12:52:49

Hi Arend,

Am 22. September 2016 16:00:36 MESZ, schrieb Arend Van Spriel <[email protected]>:
>Op 22 sep. 2016 14:52 schreef "Jörg Krause"
><[email protected]>:
>>
>> On Do, 2016-09-22 at 10:09 +0200, Arend Van Spriel wrote:
>> > 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
>> > > > > > > > > > <
>> > > > > > > > > > [email protected]>:
>> > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > > > Op 5 aug. 2016 22:46 schreef "Jörg Krause"
>> > > > > > > > > > <[email protected]>:
>> > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > > > 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].
>>
>> Stupid me! Now I used a monitor interface on a desktop to monitor the
>> traffic between the BCM43362 operating in soft-AP mode and a notebook
>> operating in managed mode.
>>
>> The BCM43362 runs the iperf server, the notebook the iperf client.
>
>Thanks.
>
>Week almost through so might next week.

Did you had some time to look at this?

Best regards
Jörg Krause

--
Diese Nachricht wurde von meinem Android-Mobiltelefon mit K-9 Mail gesendet.

2016-10-12 19:33:54

by Jörg Krause

[permalink] [raw]

Subject: Re: TCP data throughput for BCM43362

On Mi, 2016-10-12 at 21:08 +0200, Arend van Spriel wrote:

[snip]

> On 12-10-16 16:27, Jörg Krause wrote:
> >
> > It is running the iperf server. It is running in station mode as
> > well
> > as in AP mode, depending on the use case. The wireshark dump was
> > taken
> > when the bcm43362 is operating in AP mode.
> >
> > >
> > > What specs does the ARM on your custom board have?
> >
> > Which specs do you mean?
> >
> > >
> > > The trace shows that it does not do
> > > aggregation. What it does not show is whether A-MPDU was setup,
> > > ie.
> > > ADDBA message exchange. So could you create a similar capture
> > > including
> > > connection setup, ie. AUTH/ASSOC, etc.
> >
> > Yes, I can do that. Note, that I am using wpa_supplicant 2.5 for AP
> > mode operation (not hostapd).
>
> ok. unchartered territory for me. In the beacon frame I see
>
> .... ..01 = Maximum Rx A-MPDU Length: 0x1 (16383[Bytes])
> ...1 10.. = MPDU Density: 8 [usec] (0x6)
>
> In the trace it is only ~1500 bytes so no A-MPDU.

The issue is not only valid for operating the BCM43362 in AP mode, but
also in station mode. The TCP throughput is the same for both modes.

> What device is in the notebook?

It is a Broadcom 43225. However, the low TCP throughput is not specific
to this device but with all kind of devices including Smartphones,
Notebooks, PCs running the iperf client.

> Can you use 'iw list' there to obtain info.

$ iw list
Wiphy phy0
max # scan SSIDs: 4
max scan IEs length: 2257 bytes
max # sched scan SSIDs: 0
max # match sets: 0
max # scan plans: 1
max scan plan interval: -1
max scan plan iterations: 0
Retry short limit: 7
Retry long limit: 4
Coverage class: 0 (up to 0m)
Device supports RSN-IBSS.
Supported Ciphers:
* WEP40 (00-0f-ac:1)
* WEP104 (00-0f-ac:5)
* TKIP (00-0f-ac:2)
* CCMP (00-0f-ac:4)
* 00-0f-ac:10
* GCMP (00-0f-ac:8)
* 00-0f-ac:9
Available Antennas: TX 0 RX 0
Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* monitor
Band 1:
Capabilities: 0x70
HT20
Static SM Power Save
RX Greenfield
RX HT20 SGI
RX HT40 SGI
No RX STBC
Max AMSDU length: 3839 bytes
No DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 8 usec (0x06)
HT Max RX data rate: 500 Mbps
HT TX/RX MCS rate indexes supported: 0-15
Bitrates (non-HT):
* 1.0 Mbps
* 2.0 Mbps (short preamble supported)
* 5.5 Mbps (short preamble supported)
* 11.0 Mbps (short preamble supported)
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
Frequencies:
* 2412 MHz [1] (19.0 dBm)
* 2417 MHz [2] (19.0 dBm)
* 2422 MHz [3] (19.0 dBm)
* 2427 MHz [4] (19.0 dBm)
* 2432 MHz [5] (19.0 dBm)
* 2437 MHz [6] (19.0 dBm)
* 2442 MHz [7] (19.0 dBm)
* 2447 MHz [8] (19.0 dBm)
* 2452 MHz [9] (19.0 dBm)
* 2457 MHz [10] (19.0 dBm)
* 2462 MHz [11] (19.0 dBm)
* 2467 MHz [12] (19.0 dBm) (no IR)
* 2472 MHz [13] (19.0 dBm) (no IR)
* 2484 MHz [14] (disabled)
Supported commands:
* new_interface
* set_interface
* new_key
* start_ap
* new_station
* new_mpath
* set_mesh_config
* set_bss
* authenticate
* associate
* deauthenticate
* disassociate
* join_ibss
* join_mesh
* set_tx_bitrate_mask
* frame
* frame_wait_cancel
* set_wiphy_netns
* set_channel
* set_wds_peer
* probe_client
* set_noack_map
* register_beacons
* start_p2p_device
* set_mcast_rate
* set_qos_map
* connect
* disconnect
Supported TX frame types:
* IBSS: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80
0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* managed: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80
0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP/VLAN: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* mesh point: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-client: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-GO: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80
0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-device: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70
0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
Supported RX frame types:
* IBSS: 0x40 0xb0 0xc0 0xd0
* managed: 0x40 0xd0
* AP: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* AP/VLAN: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* mesh point: 0xb0 0xc0 0xd0
* P2P-client: 0x40 0xd0
* P2P-GO: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* P2P-device: 0x40 0xd0
software interface modes (can always be added):
* AP/VLAN
* monitor
interface combinations are not supported
HT Capability overrides:
* MCS: ff ff ff ff ff ff ff ff ff ff
* maximum A-MSDU length
* supported channel width
* short GI for 40 MHz
* max A-MPDU length exponent
* min MPDU start spacing
Device supports TX status socket option.
Device supports HT-IBSS.
Device supports SAE with AUTHENTICATE command
Device supports low priority scan.
Device supports scan flush.
Device supports AP scan.
Device supports per-vif TX power setting
Driver supports a userspace MPM
Device supports configuring vdev MAC-addr on create.

> >
> > >
> > > Just to confirm. You are using the firmware from linux-firmware,
> > > right?
> >
> > Right.
> >
> > >
> > > Or are you using firmware from the wiced dev kit?
> >
> > No. I guess you mean bcmdhd?
>
> You referred to 20 Mbps claim on wiced dev kit page at mouser so I
> assumed you were using that and it includes firmware. As you
> confirmed
> using firmware from linux-firmware repo this question does not
> matter.

I see! Note, that I measured >20MB throughput on the Cubietruck, which
is using the AP6210, but also the brcmfmac driver.

Best regards
Jörg Krause