Hi Bruno, you are right, Eigen3 can use OpenMP for some algorithms like matrix products PartialPivLU. But we do not use it, at least explicitly, so I do not think, it is hurt. But I will probably define EIGEN_DONT_PARALLELIZE to e sure.
Anton 2014-06-09 13:58 GMT+02:00 Bruno Chareyre <[email protected]>: > Interesting! > It seems to me that it needs more than that to be really efficient, because > eigen takes the max number of threads by default. > So that if you run -j4, parallel eigen in parallel interaction loop will > take theoretically 16 threads. Surely a perf killer if you have only 4 > threads. > There is Eigen::setNbThreads(n) for this purpose, "n" could be a runtime > variable of yade. > Another thing is to allow nested parallel loop in openmp, it is not the case > by default on most systems. > It can be enable explicitely using omp_set_nested(k). > All this needs benchmarking, too. > > Bruno > > > > On 08/06/14 23:54, [email protected] wrote: > > ------------------------------------------------------------ > revno: 4009 > committer: Anton Gladky <[email protected]> > timestamp: Sun 2014-06-08 23:32:06 +0200 > message: > Enable vectorization in eigen3-lib > > Together with vectorazation some other flags were > removed: > EIGEN_DONT_VECTORIZE > EIGEN_DONT_ALIGN > EIGEN_DISABLE_UNALIGNED_ARRAY_ASSERT > EIGEN_NO_DEBUG > > It should increase the calculation speed of some > vector-matrixes operations. > modified: > lib/base/Math.hpp > > > -- > lp:yade > https://code.launchpad.net/~yade-pkg/yade/git-trunk > > Your team Yade developers is subscribed to branch lp:yade. > To unsubscribe from this branch go to > https://code.launchpad.net/~yade-pkg/yade/git-trunk/+edit-subscription > > > > _______________________________________________ > Mailing list: https://launchpad.net/~yade-dev > Post to : [email protected] > Unsubscribe : https://launchpad.net/~yade-dev > More help : https://help.launchpad.net/ListHelp > > > > -- > _______________ > 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 > ________________ > > > _______________________________________________ > Mailing list: https://launchpad.net/~yade-dev > Post to : [email protected] > Unsubscribe : https://launchpad.net/~yade-dev > More help : https://help.launchpad.net/ListHelp > _______________________________________________ Mailing list: https://launchpad.net/~yade-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
