[LITMUS^RT] recording start real-time task

[Thijs Raets]

Hi,

The sys_release wasn't recognized by unit trace, I had to add the
sys_release type a second time in the array of the unit-trace script since
the type number was 11. I can record the task set release now but I have a
new problem now. This is my output:


.
.
.

Event ID: 7
Job: 0.0
Type: sys_release2
Time: 672784686695748

Event ID: 8
Job: 6904.1
Type: resume
Time: 672784686702656

Event ID: 9
Job: 6904.2
Type: release
Time: 672784686705186

Event ID: 10
Job: 6904.2
Type: switch_to
Time: 672784686727392

Event ID: 11
Job: 6904.3
Type: switch_away
Time: 672784686731107

Event ID: 12
Job: 6904.3
Type: completion
Time: 672784686736223

Event ID: 13
Job: 6904.4
Type: release
Time: 672785686000000

Rtspin has a period of 100ms. The resume of job 1 is ignored I only look at
release and completion. Job 2 is released but had no completion(no worries
I want soft real-time results). Job 3 only has completion time. The real
problem for me is the time difference between the release of job 4 and job
2. It's nowhere near 200ms the other jobs are released just fine, but they
are all shifted because of job 4 releasing late.(This problem only occurs
when using synchronous release)

Any ideas?

Thanks,
Thijs




2014-04-17 12:48 GMT+02:00 Thijs Raets <thijsraets at gmail.com>:

> Hi,
>
> That was exactly what I was looking for thank you! Is it possible that
> this sys_release event appears as type "resume" in my unit-trace output?
>
> Kind regards,
> Thijs
>
>
> 2014-04-17 0:15 GMT+02:00 Glenn Elliott <gelliott at cs.unc.edu>:
>
> Hi Thijs,
>>
>> Are you using synchronous releases?  (The ‘-w’ option for rtspin.)  With
>> ‘-w’, rtspin will block until the user execute’s liblitmus’s ‘release_ts’
>> (“release task set”).  Task set release records a timestamped ’sys_release’
>> event in sched_trace.  You can then discard any releases/completions that
>> occur before the sys_release timestamp.  I believe this will happen
>> naturally if you tell unit-trace to discard the first job of every task
>> with “-s 1”.
>>
>> The “experiment-scripts” package (
>> https://github.com/LITMUS-RT/experiment-scripts) can also be used to
>> analyze traces.  However, it also requires you to use its framework to set
>> up experiments (this can take some time if you need to do something out of
>> the ordinary).  The tool currently only gives you information on job
>> deadline misses, tardiness, and the amount of time tasks send blocked.
>>  However, it’s fairly easy to extend parse/sched.py to do other forms of
>> analysis, such as job response time.
>>
>> -Glenn
>>
>>
>> On Apr 16, 2014, at 12:14 PM, Thijs Raets <thijsraets at gmail.com> wrote:
>>
>> Hi,
>>
>> I'm using feather trace to monitor the rtspin task. I parsed the .bin
>> file with unit-trace and thus extracted release and completion. The problem
>> is that I also would like to record the time at which I give the order to
>> execute the rtspin task. I need this time to calculate the theoretical
>> deadlines of the different jobs since the release time of the first job
>> could have been postponed. I however do not know how time is registered
>> within feather trace. I would like to use the same reference to record the
>> start time. Where do I look?
>>
>> Thanks in advance,
>>
>> Thijs
>> _______________________________________________
>> litmus-dev mailing list
>> litmus-dev at lists.litmus-rt.org
>> https://lists.litmus-rt.org/listinfo/litmus-dev
>>
>>
>>
>> _______________________________________________
>> litmus-dev mailing list
>> litmus-dev at lists.litmus-rt.org
>> https://lists.litmus-rt.org/listinfo/litmus-dev
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.litmus-rt.org/pipermail/litmus-dev/attachments/20140422/01222405/attachment.html>