yade-dev team mailing list archive

["Sergei D." <sj2001@xxxxxxxxx>]

02.03.2011 11:55, Václav Šmilauer пишет:
> > Cause is a non-parallelised InsertionSortCollider, who need about 80% 
> > time with 4 threads.
> The cause is not (only) that it is not parallelized, but that the 
> algorithm scales worse than O(n). You see that for 1 thread collider's 
> percentage gets up with increasing n. Parallelizing the collider will 
> only have very limited effect, and I doubt it is worth the work that 
> would be necessary for that; FYI the trivial "let's sort along the 3 
> axes in parallel" does not make it any faster. v.
Agree. But scaling O(NlogN) is not so bad.. And perfomance can be 
significantly optimized now by playing with verletDist, I think. But it 
need some tries.

But what about

>  40% of collider time is spent in the "find(id1,id2)" ???

Because, if more verletDist =>  more interactions per body =>  yet more time for collider?!



--
Best regards,
Sergei D.