yade-dev team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

Thanks! Comments below.

On 26/02/14 13:33, Matthias Frank wrote:
>
>
> i have also some benchmark results:
>
> for 1 thread
> -------------------------------------------------------------------------------------------------------
>
> InsertionSortCollider                                 7
> 21314382us               51.34%
> InteractionLoop                                     200
> 14890015us               35.87%
> NewtonIntegrator                                    200
> 5084295us               12.25%
> TOTAL 41513619us              100.00%

> for 4 threads
> -------------------------------------------------------------------------------------------------------
>
> InsertionSortCollider                                 7
> 8374089us               44.57%
> InteractionLoop                                     200
> 6866564us               36.55%
> NewtonIntegrator                                    200
> 2915176us               15.52%
> TOTAL 18787178us              100.00%

>
> --------------------------------------------------------------------------------------------------------
>
> for 8 threads
> -------------------------------------------------------------------------------------------------------
>
> InsertionSortCollider                                 7
> 7577257us               39.74%
> InteractionLoop                                     200
> 6923126us               36.31%
> NewtonIntegrator                                    200
> 3186823us               16.71%
> TOTAL 19067561us              100.00%
>

You are confirming my timings.
1/ ISC scales much better than interaction loop and newton.
2/ Hyperthreading is completely useless for heavy computing tasks,
actually even bad, as your results suggest.
Benchmarking 8 threads via this technique is irrelevant for this reason.
What I would really like to see is how the collider scales with 8
non-virtual cores and more.
I think they can do that in Freiberg and Newcastle (in Grenoble as well,
in fact, I just didn't find the time).

What I need also before pushing to trunk is more testing with real
scripts, not just --performance.
I only covered a narrow range of situations with my own scripts, I would
like to be sure that it will not break in other cases.

Cheers.

Bruno