Hello Community, I just finished building an OpenMPI version with custom configuration (1.4.4) on a server. I do not have root privileges on the server.
The server already had a "default" version on OpenMPI, which seemed to be single-threaded: ompi_info | grep Thread yields Thread support: posix (mpi: no, progress: no) For my custom build, I have MPI thread support (precisely, support for MPI_THREAD_MULTIPLE): /path/to/Custom/OpenMPI/bin/ompi_info | grep Thread yields Thread support: posix (mpi: yes, progress: no) Thus, I run my application as: /path/to/Custom/OpenMPI/bin/mpirun [options]... In my application, I do make a check for whether I am getting MPI_THREAD_MULTIPLE support or not: MPI_Init_thread(&argc, &argv, desired_thread_support, &provided_thread_support);/*Need provided_thread_support = desired_thread_support*/ printf ("MPI: Requested thread support: %d, MPI thread support received: %d\n", MPI_THREAD_MULTIPLE, provided_thread_support); When I run the application, I get: MPI: Requested thread support: 3, MPI thread support received: 0 I have tried lot of things, and I am not sure why this is the case. At the beginning of the shell script which contains /path/to/Custom/OpenMPI/bin/mpirun [options]..., I set the paths, and LD_LIBRARY_PATH: PATH=/home/raid/private/Customizations_NODELETE/OpenMPI-1.4.4/bin:$PATH export LD_LIBRARY_PATH=/home/raid/private/Customizations_NODELETE/gcc-4.6/lib64:/home/Morpheus/.CustomInstalledPrograms/OpenMPI-1.4.4/lib:/home/raid/private/Customizations_NODELETE/gcc-4.6/lib32 So, I think that the correct version of mpirun is being used. Can someone tell me why I cannot get MPI_THREAD_MULTIPLE support? I have the same OpenMPI version on my notebook, which does provide me with MPI_THREAD_MULTIPLE. Thanks a lot. Best, Devendra