[OMPI users] Open question: do you use Open MPI mirror web sites?

You may or may not realize it, but Open MPI has several mirror web sites around the world -- see https://www.open-mpi.org/community/mirrors/ One of the primary reasons we started the web site mirror program was to help out those for whom bandwidth is expensive. I.e., the idea was that users cou

[OMPI users] Parallel Backtracking in MPI

I'm currently working on a project that utilizes MPI in order to distribute the calculating of a game tree across multiple MPI nodes. In order to do this, we require the use of a backtracking algorithm. We've yet to find any that support the parallelism of MPI and are wondering if there exists any

[OMPI users] OpenMP explicit thread affinity with MPI

Hi, I am trying to do something like below with OpenMPI and OpenMP (threads). [image: Inline image 1] I was trying to use the explicit thread affinity with GOMP_CPU_AFFINITY environment variable as described here ( https://gcc.gnu.org/onlinedocs/libgomp/GOMP_005fCPU_005fAFFINITY.html). However,

Re: [OMPI users] OpenMP explicit thread affinity with MPI

Why don’t you have your application look at the OMPI_COMM_WORLD_LOCAL_RANK envar, and then use that to calculate the offset location for your threads (i.e., local rank 0 is on socket 0, local rank 1 is on socket 1, etc.). You can then putenv the correct value of the GOMP envar > On Jun 28, 201

Re: [OMPI users] OpenMP explicit thread affinity with MPI

Can't you simply export OMP_PROC_BIND=1 assuming mpirun has the correct command line (e.g. correctly bind tasks on x cores so the x OpenMP threads will be individually bound to each core), each is bound to disjoint cpusets, so i guess GOMP will bind OpenMP threads within the given cpuset.