[USRP-users] about 10 Gig ethernet configuration

Michael West michael.west at ettus.com
Fri Oct 23 15:36:33 EDT 2015


Hi Sanjoy,

The CPU governor is critical for the higher rates.  You should figure out
how to make it stay on performance.

The cable is also very important.  We found in our own testing that the
longer the copper cable is, the more prone to failure.  The 1m copper cable
we tested worked well, but the 3m and 5m copper cables we tested resulted
in dropped packets.  We use fibre any time we need a cable longer than 1m.

I believe if you get the proper cable and get the CPU governor set to
performance, you will be able to run at the higher rates.

Regards,
Michael

On Fri, Oct 23, 2015 at 12:21 PM, Sanjoy Basak <sanjoybasak14 at gmail.com>
wrote:

> Hi Michael, Neel and Marcus,
>
> Thanks a lot for the suggestions. I tried each of those.
> I updated the kernel to 3.19.0-31-generic.
>
> CPU governors, I set to performance as instruction given in this link.
> http://files.ettus.com/manual/page_usrp_x3x0_config.html#x3x0cfg_hostpc_pwr
> Now, after setting it to performance and restarting, if I check with
> cpu-freq, I find all governers are set at performance. But after a
> while(5/10 mins later) if I check again cpu-freq info, I see all governers
> are set to powersave.
> Could you please tell me why and how to configure it properly?
>
> I tried with benchmark_rate to check the performance. With tx-rate till
> 200 MSps I do not get any overflow/underflow. However with rx-rate
> 25/50/100 MSps I get drop of packets. I made a direct connection from
> computer to the X310. No switch is used.
>
> On the contrary with shorter(copper) cable at 1Gig interface I do not get
> any drop of packets at 25MSps (on both tx_rate and rx_rate).
> Is 3m copper cable really bad?
>
> We don't have fibre cable right now. We already ordered. I hope we will
> get it next week and check how it is. We don't have any SFP+ 10 Gig
> interface. So can't really test 10 gig interface with short 10 gig copper
> cable.
>
> These are the benchmark_rate results for 10 Gig interface
>
>
> Testing receive rate 25.000000 Msps on 1 channels
> DDDDDDDD
> Benchmark rate summary:
>   Num received samples:    249845308
>   Num dropped samples:     15968
>   Num overflows detected:  0
>   Num transmitted samples: 0
>   Num sequence errors:     0
>   Num underflows detected: 0
>
>
> Testing receive rate 100.000000 Msps on 1 channels
> DDDDDDDDDDDDDDDDDDDDD
> Benchmark rate summary:
>   Num received samples:    999934124
>   Num dropped samples:     41916
>   Num overflows detected:  0
>   Num transmitted samples: 0
>   Num sequence errors:     0
>   Num underflows detected: 0
>
>  I also used this command
> sudo ethtool -C eth2 rx-usecs 16 rx-frames 20
>
> Please let me know what you think occurring the problem and
> whether replacing copper cable with short fibre cable solves the problem.
>
> Best regards
> Sanjoy
>
>
> On Wed, Oct 21, 2015 at 12:27 PM, Marcus Müller <
> usrp-users at lists.ettus.com> wrote:
>
>> Hi Sanjoy,
>>
>> furthermore, and I found that to be crucial on my system, you should make
>> sure that your 10GE card doesn't generate an interrupt for every packet it
>> receives (your application will pull these packets as fast as possible,
>> anyway).
>> On linux, you'd do
>>
>> sudo ethtool -c {name of ethernet interface, e.g. eth1}
>>
>> to see the coalescing options available with your device and kernel
>> version,
>> and modify a setting using
>>
>> sudo ethtool -C {name of ethernet interface, e.g. eth1} {name of setting}
>> {new value of setting}
>>
>> For example, I set "rx_usecs" (microseconds to wait between triggering an
>> interrupt) to 16, and "rx_frames" to 20 or so -- your milage might vary,
>> depending on your application, OS and also a few hardware factors.
>>
>> Best regards,
>> Marcus
>>
>>
>> On 19.10.2015 21:56, Michael West via USRP-users wrote:
>>
>> Also, check the CPU governor and make sure it is set to "performance".
>>
>> Your output indicates frame errors on the interface, which could be due
>> to the cable.  If possible, try using a shorter copper cable or switch to a
>> fibre cable.  With 10 GbE over copper, the shorter the better.  If you need
>> the length, you should be using fibre.
>>
>> If you still have issues, please provide a little more information:  Are
>> you connected directly with the X310 or through a switch?  How are you
>> testing the performance?  Are you using your own application or
>> benchmark_rate?  If your own application, what is it doing with the
>> received data (processing it with the same thread or different thread,
>> saving to disk, etc...)?
>>
>> Regards,
>> Michael
>>
>> On Mon, Oct 19, 2015 at 12:51 PM, Neel Pandeya via USRP-users <
>> <usrp-users at lists.ettus.com>usrp-users at lists.ettus.com> wrote:
>>
>>> Hello Sanjoy:
>>>
>>> That Intel X520 10GbE card with Ubuntu 14.04.3 should be working well
>>> for you.
>>>
>>> Could you try upgrading to kernel 3.16 or 3.19, and let us know your
>>> results?
>>>
>>> To upgrade to kernel 3.16, run "sudo apt-get install
>>> linux-generic-lts-utopic".
>>>
>>> To upgrade to kernel 3.19, run "sudo apt-get install
>>> linux-generic-lts-vivid".
>>>
>>> After the upgrade, be sure to reboot the system.
>>>
>>> Also, check that you have the CPU governors set to "performance", and
>>> that you have the highest clock rate set.
>>>
>>> --Neel
>>>
>>>
>>>
>>> On 19 October 2015 at 12:03, Sanjoy Basak via USRP-users <
>>> <usrp-users at lists.ettus.com>usrp-users at lists.ettus.com> wrote:
>>>
>>>> Hi Experts,
>>>> We recently bought a 10 Gig ethernet card (X510-DA2) and Twinaxial-Kabel
>>>> SFP+ M SFP+ M 3,0m. I installed it in our pc (OS: Ubuntu Mate 14.04.3 LTS)
>>>> and can communicate with X310/SBX-120 properly. However, the performance we
>>>> are getting is quite poor. I am getting dropped packets (D O) mostly at
>>>> 25,50 MSps and goes quite crazy at 100 MSps and sometimes even at lower
>>>> sample rates.
>>>> Previously I tested with 1 Gig ethernet, at 25 MSps I could stream
>>>> without any drop/late packet or underrun.
>>>> The CPU uses or network uses is also not reaching 100%.
>>>>
>>>> Could you please tell me what to check/correct so I can stream at 100
>>>> MSps without any error?
>>>>
>>>> I am putting the ifconfig and ethtool results and the kernel version(
>>>> 3.16.0-30-generic)
>>>>
>>>> eth2      Link encap:Ethernet  HWaddr 90:e2:ba:a6:a9:dd
>>>>           inet6 addr: fe80::92e2:baff:fea6:a9dd/64 Scope:Link
>>>>           UP BROADCAST MULTICAST  MTU:9000  Metric:1
>>>>           RX packets:4530726 errors:146 dropped:0 overruns:0 frame:146
>>>>           TX packets:6811057 errors:0 dropped:0 overruns:0 carrier:0
>>>>           collisions:0 txqueuelen:1000
>>>>           RX bytes:26331306938 (26.3 GB)  TX bytes:35856233935 (35.8 GB)
>>>>
>>>> Settings for eth2:
>>>> Supported ports: [ FIBRE ]
>>>> Supported link modes:   10000baseT/Full
>>>> Supported pause frame use: No
>>>> Supports auto-negotiation: No
>>>> Advertised link modes:  10000baseT/Full
>>>> Advertised pause frame use: No
>>>> Advertised auto-negotiation: No
>>>> Speed: 10000Mb/s
>>>> Duplex: Full
>>>> Port: Other
>>>> PHYAD: 0
>>>> Transceiver: external
>>>> Auto-negotiation: off
>>>> Cannot get wake-on-lan settings: Operation not permitted
>>>> Current message level: 0x00000007 (7)
>>>>       drv probe link
>>>> Link detected: yes
>>>>
>>>> Our computer config is:
>>>> Processor: 12*Intel(R) Xeon (R) CPU E5-2620 v3 @2.40 GHz
>>>> RAM: 65871 MB
>>>> SSD raid 5
>>>>
>>>>
>>>> Best regards
>>>> Sanjoy
>>>>
>>>> _______________________________________________
>>>> USRP-users mailing list
>>>> USRP-users at lists.ettus.com
>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>>>
>>>>
>>>
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>>
>>
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