Re: Latency problem in rtai-4.0 with kernel 3.5.7

Hi Paolo,

i have logged Timestamp data.it shows inconsistent result. Please find 
attached file for more details.

if you get any clue from this please let me know.


-- 
Thanks & Regards,

*Sameer Zungare*
+91 9021918228
*/iASYS/*
*Product Development Center*
401 A/2, Nano Space
Baner-Pashan link road, Baner
Pune 411045, India
Ph. +91 96234 47255 ext. xxx
www.iasys.co.in

__
On 04/06/2016 3:53 PM, Paolo Mantegazza wrote:
> On 04/06/2016 10:57 AM, Sameer wrote:
>> Hi Paolo,
>>
>> Ok,But why i got undeterministic behavior in my application.suddenly 
>> i got 3-5 sec delay even it is hard real time.
>>
>
> For that I've no clue, at least as the tests I carried out to verify 
> it, likely more demanding than yours, do not show the problem you 
> mentioned.
> In most cases experience shows that there could be configurations 
> problems at the hardware/Linux level.
> What said does not mean that RTAI is not the culprit, but simply that 
> there has been no changes to RTAI, with respect to the working 
> versions you are using, which can hint me any clue to help solving 
> your problem.
> I can just suggest you to try using the latest VULCANO CVS, close to 
> become rtai-5.
>
> Paolo
>> -- 
>> Thanks & Regards,
>>
>> *Sameer Zungare*
>> +91 9021918228
>> */iASYS/*
>> *Product Development Center*
>> 401 A/2, Nano Space
>> Baner-Pashan link road, Baner
>> Pune 411045, India
>> Ph. +91 96234 47255 ext. xxx
>> www.iasys.co.in
>>
>> __
>> On 04/06/2016 1:53 PM, Paolo Mantegazza wrote:
>>> On 04/06/2016 09:27 AM, Sameer wrote:
>>>> Hi Paolo,
>>>>
>>>> yes,in our application we used start_rt_timer() call.There are 4 
>>>> real time tasks with different priorities 1,5,6,7.
>>>>
>>> Then when you start your application there is a timer reset and what 
>>> is running already will be stalled for a while, so the overruns. 
>>> Therefore what is important is that the overruns number does not 
>>> change after the timer has been restarted.
>>> That's one of the reason for which in 5.0 hard timer initializations 
>>> by users are muted and the timer managed directly just by the 
>>> scheduler, in oneshot mode only.
>>> Paolo--
>>>> Thanks & Regards,
>>>>
>>>> *Sameer Zungare*
>>>> +91 9021918228
>>>> */iASYS/*
>>>> *Product Development Center*
>>>> 401 A/2, Nano Space
>>>> Baner-Pashan link road, Baner
>>>> Pune 411045, India
>>>> Ph. +91 96234 47255 ext. xxx
>>>> www.iasys.co.in
>>>>
>>>> __
>>>> On 04/06/2016 12:46 PM, Paolo Mantegazza wrote:
>>>>> Does your application do start_rt_timer? Does your application  
>>>>> have tasks at priority 0?
>>>>> Paolo
>>>>>
>>>>> On 04/06/2016 07:27 AM, Sameer wrote:
>>>>>> hi Paolo,
>>>>>>     Thanks for reply.
>>>>>>
>>>>>>     i run latency test alone. it shows overrun count 0 but 
>>>>>> whenever i load my application overrun start to increment.
>>>>>>
>>>>>>     Please find attached latency test result.
>>>>>>
>>>>>> -- 
>>>>>> Thanks & Regards,
>>>>>>
>>>>>> *Sameer Zungare*
>>>>>> +91 9021918228
>>>>>> */iASYS/*
>>>>>> *Product Development Center*
>>>>>> 401 A/2, Nano Space
>>>>>> Baner-Pashan link road, Baner
>>>>>> Pune 411045, India
>>>>>> Ph. +91 96234 47255 ext. xxx
>>>>>> www.iasys.co.in
>>>>>>
>>>>>>
>>>>>> On 04/05/2016 8:36 PM, Paolo Mantegazza wrote:
>>>>>>> You should run the latency test alone and check if the 4 ms 
>>>>>>> latency appears periodically.
>>>>>>> Paolo
>>>>>>>
>>>>>>> On 04/05/2016 04:49 PM, Sameer wrote:
>>>>>>>> hi,
>>>>>>>>
>>>>>>>> Please find attached latency test result.
>>>>>>>>
>>>>>>>> Iam facing latency problem in my real time application.I have 4 
>>>>>>>> real time task exucting in user space at 10ms & one kernel 
>>>>>>>> module task which is executing at 1ms.
>>>>>>>>
>>>>>>>> my application is randomly stuck for 2-3 sec. sometimes greater 
>>>>>>>> than this also. simulataneously i run latency test it also 
>>>>>>>> shows overruns count more than 200.it is not deterministic 
>>>>>>>> behaviour.
>>>>>>>> my current machine has below configuration
>>>>>>>>
>>>>>>>> 1.Ubunbtu-12.04
>>>>>>>> 2.RTAI-4.0
>>>>>>>> 3.kernel 3.5.7
>>>>>>>> 4.Cpu core -Intel Pentium 4.
>>>>>>>> 5.Timer-tsc.
>>>>>>>> 6.No. of core-1.
>>>>>>>>
>>>>>>>> The same applications work deterministic in my older system 
>>>>>>>> which has kernel 2.6.23 & rtai-3.9 & centos distro with same PC.
>>>>>>>>
>>>>>>>>
>>>>>>>> Is there any problem with kernel or rtai or ubuntu or kernel 
>>>>>>>> configuaration?
>>>>>>>>
>>>>>>>> Please let me know any solution for this problem.
>>>>>>>> -- 
>>>>>>>> Thanks & Regards,
>>>>>>>>
>>>>>>>> *Sameer Zungare*
>>>>>>>> +91 9021918228
>>>>>>>> */iASYS/*
>>>>>>>> *Product Development Center*
>>>>>>>> 401 A/2, Nano Space
>>>>>>>> Baner-Pashan link road, Baner
>>>>>>>> Pune 411045, India
>>>>>>>> Ph. +91 96234 47255 ext. xxx
>>>>>>>> www.iasys.co.in
>>>>>>>
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