Re: [Starpu-devel] Query about profiling data

[Nathalie Furmento <nathalie.furmento@labri.fr>]

You can find informations about the starpu_worker_profiling_info
structure here:

http://runtime.bordeaux.inria.fr/StarPU/starpu.html#Worker-feedback
http://runtime.bordeaux.inria.fr/StarPU/starpu.html#struct-starpu_005fworker_005fprofiling_005finfo

Cheers,

Nathalie

On Dec 01, 22:15, ASUDE ASUDE wrote:
> Hello Nathalie,
>  Thanks for the reply.
> But the numbers below still don't add up, not able to interpret them
> correctly. How are these execution times to be interpreted?
> 
> Executing on CPU 0
> Avg. delay : 41.16 us
> Avg. length : 2613.87 us
> Worker CUDA 0 (GeForce GTX 470):
>         total time : 2.95 ms
>         exec time  : 0.00 ms (0.00 %)
>         blocked time  : 0.00 ms (0.00 %)
> Worker CPU 0:
>         total time : 2.96 ms
>         exec time  : 5.44 ms (183.80 %)
>         blocked time  : 0.00 ms (0.00 %)
> 
> Executing on CPU 0
> Avg. delay : 37.06 us
> Avg. length : 2736.63 us
> Worker CUDA 0 (GeForce GTX 470):
>         total time : 2.86 ms
>         exec time  : 0.00 ms (0.00 %)
>         blocked time  : 0.00 ms (0.00 %)
> Worker CPU 0:
>         total time : 2.87 ms
>         exec time  : 5.52 ms (192.56 %)
>         blocked time  : 0.00 ms (0.00 %)
> 
> Executing =CUDA 0 (GeForce GTX 470)
> Avg. delay : 647.63 us
> Avg. length : 378.75 us
> Worker CUDA 0 (GeForce GTX 470):
>         total time : 1.15 ms
>         exec time  : 0.84 ms (72.70 %)
>         blocked time  : 0.00 ms (0.00 %)
> Worker CPU 0:
>         total time : 1.16 ms
>         exec time  : 0.00 ms (0.00 %)
>         blocked time  : 0.00 ms (0.00 %)
> 
> 
> On Thu, Dec 1, 2011 at 6:46 PM, Nathalie Furmento <
> nathalie.furmento@labri.fr> wrote:
> 
> > **
> > Hello,
> >
> >
> > On 01/12/2011 19:16, ASUDE ASUDE wrote:
> >
> > Hello,
> > I have a question about interpreting the profiling data for tasks and
> > workers which I get from starpu.
> > My setup shows
> > StarPU has found :
> >         1 CPU cores
> >                 CPU 0
> >         1 CUDA devices
> >                 CUDA 0 (GeForce GTX 470)
> > on starpu_machine_display.
> >
> > To explain a little about my application - When I execute it w/o profiling
> > code added, I get below messages printed on my console:
> > Executing on CPU 0
> > Executing =CUDA 0 (GeForce GTX 470)
> > Executing =CUDA 0 (GeForce GTX 470)
> >
> > I have for loop which calls the starpu function which creates/submits the
> > task for 3 times in loop, so above 3 messages.
> > Sometimes I get below:
> > Executing =CUDA 0 (GeForce GTX 470)
> > Executing on CPU 0
> > Executing on CPU 0
> >
> > Does that mean I means starpu assigns my 3 tasks for execution to CPU 0
> > device, CUDA 0 device ,CUDA 0 device in first execution and
> > CUDA 0 device,CPU 0 device ,CPU 0 device in second execution?
> >
> >
> > Yes.
> >
> >
> > Then I added the profiling code as I understood from the profiling example
> > at StarPU/examples/profiling/profiling.c
> >
> > Now I get below times printed on console
> >
> > Executing on CPU 0
> > Avg. delay : 41.16 us
> > Avg. length : 2613.87 us
> > Worker CUDA 0 (GeForce GTX 470):
> >         total time : 2.95 ms
> >         exec time  : 0.00 ms (0.00 %)
> >         blocked time  : 0.00 ms (0.00 %)
> > Worker CPU 0:
> >         total time : 2.96 ms
> >         exec time  : 5.44 ms (183.80 %)
> >         blocked time  : 0.00 ms (0.00 %)
> >
> > Executing on CPU 0
> > Avg. delay : 37.06 us
> > Avg. length : 2736.63 us
> > Worker CUDA 0 (GeForce GTX 470):
> >         total time : 2.86 ms
> >         exec time  : 0.00 ms (0.00 %)
> >         blocked time  : 0.00 ms (0.00 %)
> > Worker CPU 0:
> >         total time : 2.87 ms
> >         exec time  : 5.52 ms (192.56 %)
> >         blocked time  : 0.00 ms (0.00 %)
> >
> > Executing =CUDA 0 (GeForce GTX 470)
> > Avg. delay : 647.63 us
> > Avg. length : 378.75 us
> > Worker CUDA 0 (GeForce GTX 470):
> >         total time : 1.15 ms
> >         exec time  : 0.84 ms (72.70 %)
> >         blocked time  : 0.00 ms (0.00 %)
> > Worker CPU 0:
> >         total time : 1.16 ms
> >         exec time  : 0.00 ms (0.00 %)
> >         blocked time  : 0.00 ms (0.00 %)
> >
> >
> > My question is for above case, If it says first task is Executing on CPU
> > 0, why do I get non-zero execution time for  "Worker CUDA 0"
> > and other way round i.e. when it says Executing =Cuda 0 , why do I see a
> > Worker CPU 0?
> >
> >
> > You see all the workers here, the one who is executing your task, and who
> > has an non-zero exec time and the other one.
> >
> >
> > Also another question is then in this profiling case, execution times dont
> > add up or how to make sense of those times displayed above?
> >
> > Slightly confused about the terminology - Task, Worker ?
> >
> >
> > As explained in the glossary,
> > http://runtime.bordeaux.inria.fr/StarPU/starpu.html#Glossary
> >
> > A *task* represents a scheduled execution of a codelet on some data
> > handles.
> > A *worker* execute tasks. There is typically one per CPU computation core
> > and one per accelerator (for which a whole CPU core is dedicated).
> >
> >  A different/unrelated question I have is, while reading the handbook, I
> > see this kind of info -
> > How do I get this kind of online prformacne data for my starpu app:
> >
> > StarPU has found :
> >              3 CUDA devices
> >                      CUDA 0 (Tesla C2050 02:00.0)
> >                      CUDA 1 (Tesla C2050 03:00.0)
> >                      CUDA 2 (Tesla C2050 84:00.0)
> >      from    to RAM          to CUDA 0       to CUDA 1       to CUDA 2
> >      RAM     0.000000        5176.530428     5176.492994     5191.710722
> >      CUDA 0  4523.732446     0.000000        2414.074751     2417.379201
> >      CUDA 1  4523.718152     2414.078822     0.000000        2417.375119
> >      CUDA 2  4534.229519     2417.069025     2417.060863     0.000000
> >
> > What are these numbers RAM to CUDA 0 is it data transfer time in
> > milliseconds or something?
> > How do I obtain this kind of Bus related info from RAM to CUDA 0 etc...
> > What code changes?
> >
> >
> > The numbers represent the bandwidths between the different workers.
> >
> > Regards,
> >
> > Nathalie
> >
> >

-- 
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Dr Nathalie Furmento                         Ingénieur de recherche CNRS
Centre de Recherche INRIA Bordeaux Sud-Ouest http://www.labri.fr/~furmento/
351 cours de la Libération, Bât A29          Tel: +33 (0)5 24 57 41 20
33405 Talence cedex, FRANCE                  Fax: +33 (0)5 24 57 40 41
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