[etherlab-users] Data logging service dropping data

[Johnathan Van Why]

On Wed, Sep 11, 2013 at 12:32 AM, Richard Hacker <ha at igh-essen.com> wrote:
> Can you find anything in the logs for dlsd?

I am having trouble finding the DLS log files. I see the file
"logging" in the job directory, but it is empty.

Do you know where I can find any log files?

Thank You,
Johnathan Van Why
Dynamic Robotics Laboratory
Oregon State University

> Am 09/09/2013 08:04 PM, schrieb Johnathan Van Why:
>
>> On Mon, Sep 9, 2013 at 7:39 AM, Richard Hacker <ha at igh-essen.com> wrote:
>>>
>>>
>>> Are you using a multi-processor system? If so, can try using HPET
>>> (although this timing system is buggy by design - was developed together
>>> with Microsoft ;) )
>>
>>
>> I switched to the HPET, and it still drops data.
>>
>> Thank You,
>> Johnathan Van Why
>> Dynamic Robotics Laboratory
>> Oregon State University
>>
>>> Am 09/06/2013 09:25 PM, schrieb Johnathan Van Why:
>>>
>>>> On Thu, Sep 5, 2013 at 11:38 PM, Richard Hacker <ha at igh-essen.com>
>>>> wrote:
>>>>>
>>>>>
>>>>> What is you underlying real-time operating system?
>>>>
>>>>
>>>>
>>>> I am doing my testing on Linux, patched with PREEMPT_RT for realtime.
>>>>
>>>>> The DLS has a problem when the RT system influences time on the PC.
>>>>> This has
>>>>> been experienced with RTAI.
>>>>>
>>>>> Ways to fix it? Watch the system's clock while the control system is
>>>>> loaded
>>>>> and make sure it is not "pulled" in any way.
>>>>
>>>>
>>>>
>>>> I have confirmed that there is no clock drift (note: the kernel's
>>>> clocksource is the TSC). I disabled NTP and re-ran the test, with the
>>>> same results (lost data and no clock drift).
>>>>
>>>> Do you have any other ideas?
>>>>
>>>> Thank you for the help,
>>>> Johnathan Van Why
>>>> Dynamic Robotics Laboratory
>>>> Oregon State University
>>>>
>>>>> Am 09/06/2013 04:33 AM, schrieb Johnathan Van Why:
>>>>>>
>>>>>>
>>>>>>
>>>>>> We have been benchmarking EtherLab (we're considering switching to it
>>>>>> as our robot control system), and have noticed that the Data Logging
>>>>>> Service has been dropping data. We created over 100 independent
>>>>>> sources in a Simulink model, deployed to EtherLab, and logged all
>>>>>> sources at 1 kHz (over 400 KB/s total).
>>>>>>
>>>>>> After looking at the log data, we noticed that a significant amount of
>>>>>> data was dropped. Every 15 minutes, the time variable would jump by 3
>>>>>> minutes; the total data we collected was significantly less than we
>>>>>> expected for the duration of the run.
>>>>>>
>>>>>> Is this a known issue? Are we asking too much of the Data Logging
>>>>>> Service? Is there anything we can try in order to obtain reliable
>>>>>> logging at this data rate?
>>>>>>
>>>>>> Thank you for any help,
>>>>>> Johnathan Van Why
>>>>>> Dynamic Robotics Laboratory
>>>>>> Oregon State University
>>>>>> _______________________________________________
>>>>>> etherlab-users mailing list
>>>>>> etherlab-users at etherlab.org
>>>>>> http://lists.etherlab.org/mailman/listinfo/etherlab-users
>>>>>>
>>>>>
>>>>> Mit freundlichem Gruß
>>>>>
>>>>> Richard Hacker
>>>>>
>>>>> --
>>>>>
>>>>> ------------------------------------------------------------------------
>>>>>
>>>>> Richard Hacker M.Sc.
>>>>> richard.hacker at igh-essen.com
>>>>> Tel.: +49 201 / 36014-16
>>>>>
>>>>> Ingenieurgemeinschaft IgH
>>>>> Gesellschaft für Ingenieurleistungen mbH
>>>>> Heinz-Bäcker-Str. 34
>>>>> D-45356 Essen
>>>>>
>>>>> Amtsgericht Essen HRB 11500
>>>>> USt-Id.-Nr.: DE 174 626 722
>>>>> Geschäftsführung:
>>>>> - Dr.-Ing. T. Finke,
>>>>> - Dr.-Ing. W. Hagemeister
>>>>> Tel.: +49 201 / 360-14-0
>>>>> http://www.igh-essen.com
>>>>>
>>>>>
>>>>> ------------------------------------------------------------------------
>>>
>>>
>>>
>>> Mit freundlichem Gruß
>>>
>>> Richard Hacker
>>>
>>> --
>>> ------------------------------------------------------------------------
>>>
>>> Richard Hacker M.Sc.
>>> richard.hacker at igh-essen.com
>>> Tel.: +49 201 / 36014-16
>>>
>>> Ingenieurgemeinschaft IgH
>>> Gesellschaft für Ingenieurleistungen mbH
>>> Heinz-Bäcker-Str. 34
>>> D-45356 Essen
>>>
>>> Amtsgericht Essen HRB 11500
>>> USt-Id.-Nr.: DE 174 626 722
>>> Geschäftsführung:
>>> - Dr.-Ing. T. Finke,
>>> - Dr.-Ing. W. Hagemeister
>>> Tel.: +49 201 / 360-14-0
>>> http://www.igh-essen.com
>>>
>>> ------------------------------------------------------------------------
>
>
> Mit freundlichem Gruß
>
> Richard Hacker
>
> --
> ------------------------------------------------------------------------
>
> Richard Hacker M.Sc.
> richard.hacker at igh-essen.com
> Tel.: +49 201 / 36014-16
>
> Ingenieurgemeinschaft IgH
> Gesellschaft für Ingenieurleistungen mbH
> Heinz-Bäcker-Str. 34
> D-45356 Essen
>
> Amtsgericht Essen HRB 11500
> USt-Id.-Nr.: DE 174 626 722
> Geschäftsführung:
> - Dr.-Ing. T. Finke,
> - Dr.-Ing. W. Hagemeister
> Tel.: +49 201 / 360-14-0
> http://www.igh-essen.com
>
> ------------------------------------------------------------------------