Hybrid MPI/OpenMP parallelization in FETI-DP methods

We present an approach to hybrid MPI/OpenMP parallelization in FETIDP methods using OpenMP with PETSc in the finite element assembly and using the shared memory parallel direct solver Pardiso in the FETI-DP solution phase. Our approach thus uses OpenMP parallelization on subdomains and MPI in between subdomains. We investigate the efficiency of this approach for a benchmark problem from two dimensional nonlinear hyperelasticity. We observe good scalability for up to 4 threads for each MPI rank on a state-of-the-art Ivy Bridge architecture and incremental improvements for up to 10 OpenMP threads for each MPI rank.