Hello Martin I am using openblas installed using spack. openmp seems to be disabled
[email protected]%gcc@6~openmp+pic+shared arch=linux-opensuse20161217-x86_64 Using export OMP_NUM_THREADS=1 does the trick. Now I see about 100% cpu for each process. Thanks a lot praveen PS: I also disabled hyperthreading in the bios. Is there any benefit of using this ? On Thu, Dec 29, 2016 at 4:04 PM, Martin Kronbichler < [email protected]> wrote: > Hi Praveen, > > Do you happen to use a BLAS that uses threading? I recommend switching to > non-threaded BLAS (or "export OMP_NUM_THREADS=1"). deal.II applies > threading on a higher level and a threaded BLAS is counter-productive in > 98% of cases. > > Best, > Martin > > On 29.12.2016 11 <0291%20220%201611>:30, Praveen C wrote: > > Hello Daniel > > I recompiled dealii without threads. > > When I run step-40 single process > > ./step-40 > > I see upto 2000% cpu usage during cycle 7 when viewed in top. > > Best > praveen > > On Thu, Dec 29, 2016 at 3:51 PM, Daniel Arndt < > [email protected]> wrote: > >> Praveen, >> >> unsigned int n_threads = 1; >>> >>> Utilities::MPI::MPI_InitFinalize mpi_initialization (argc, argv, >>> n_threads); >>> >>> >>> But when I run this code, each process is using 1700% of CPU. The code >>> does not progress in its iterations also. What am I doing wrong ? >>> >> This looks correct. Can you verify that you don't have that problem when >> you are running step-9 (for WorkStream) and step-40 (for MPI)? >> >> Do you have a minimal working example that shows this problem? >> >> Best, >> Daniel >> >>> -- >> The deal.II project is located at <http://www.dealii.org/> >> http://www.dealii.org/ >> For mailing list/forum options, see >> <https://groups.google.com/d/forum/dealii?hl=en> >> https://groups.google.com/d/forum/dealii?hl=en >> --- >> You received this message because you are subscribed to the Google Groups >> "deal.II User Group" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see https://groups.google.com/d/ > forum/dealii?hl=en > --- > You received this message because you are subscribed to the Google Groups > "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see https://groups.google.com/d/ > forum/dealii?hl=en > --- > You received this message because you are subscribed to the Google Groups > "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
