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Re: Regression in ForceResetter?

 

Wait...
Now I realize that the timings are weird. Real times are the same, relative
times are different.
It could be that the counting is wrong. Something system/hardware dependent.
We have troubles with openMP at the moment. So forget it.
Thanks for the link anyway Anton.
B

On 15 September 2016 at 19:42, Anton Gladky <gladky.anton@xxxxxxxxx> wrote:

> Hi Bruno,
>
> the only more-less relevant commit is the following [1]. Try to comment
> that line and check, whether the regression is no more visible. If it
> is so, that problem (described in commit log) should be solved by
> more elegant way.
>
> [1] https://github.com/yade/trunk/commit/07940b52ac31597c07d9d98f289131
> 1d7e6d8e0e
>
> Cheers
>
> Anton
>
>
> 2016-09-15 19:23 GMT+02:00 Bruno Chareyre <bruno.chareyre@xxxxxxxxxxxxxxx
> >:
> > Hello all,
> >
> > I just noticed something I don't think I've ever seen before.
> > I'm wondering if some recent changes in force containers (I've seen some
> by
> > Anton IIRC) could explain that.
> > Below are the outputs of "yade --performance" and "yade -j6
> --performance"
> > (same build).
> > With -j1 the force resetter takes 3.55% of the total cpu time, not
> > negligible but ok, we can live with that.
> > With -j6 the absolute time it takes is multiplied by 3 almost, reaching
> 21%
> > in terms of rel. time. This is huge and seriously degradate the
> performance
> > of the parallel run.
> >
> > Could someone confirm this?
> >
> > Bruno
> > ______________________
> > 1 CORE
> >
> > number of bodies 47323
> >
> > Elapsed  66.9550299644  sec
> > Performance  20.9095567688  iter/sec
> > Extrapolation on 1e5 iters  1.32847281675  hours
> > =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*
> > Name Count                 Time            Rel. time
> > ------------------------------------------------------------
> -------------------------------------------
> > ForceResetter                                      1400 2373474us
> > 3.55%
> > InsertionSortCollider                                39 4636343us
> > 6.93%
> > InteractionLoop                                    1400 49261433us
> > 73.62%
> > NewtonIntegrator                                   1400 10642155us
> > 15.90%
> > TOTAL 66913407us              100.00%
> > _______________________
> > 6 CORES
> >
> > number of bodies 47323
> >
> > Elapsed  29.4499371052  sec
> > Performance  47.5383018646  iter/sec
> > Extrapolation on 1e5 iters  0.584324148912  hours
> > =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*
> > Name Count                 Time            Rel. time
> > ------------------------------------------------------------
> -------------------------------------------
> > ForceResetter                                      1400 6370788us
> > 21.66%
> > InsertionSortCollider                                39 1957601us
> > 6.66%
> > InteractionLoop                                    1400 13912593us
> > 47.30%
> > NewtonIntegrator                                   1400 7174500us
> > 24.39%
> > TOTAL 29415483us              100.00%
> >
> > --
> > _______________
> > Bruno Chareyre
> > Associate Professor
> > ENSE³ - Grenoble INP
> > Lab. 3SR
> > BP 53
> > 38041 Grenoble cedex 9
> > Tél : +33 4 56 52 86 21
> > Fax : +33 4 76 82 70 43
> > ________________
> >
> > Email too brief?
> > Here's why! http://emailcharter.org
> >
> >
> >
> > _______________________________________________
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