COMPARISON OF MULTI-FRONTAL AND ALTERNATING DIRECTION PARALLEL HYBRID MEMORY IGRM DIRECT SOLVER FOR NON-STATIONARY SIMULATIONS.

Three-dimensional isogeometric analysis (IGA-FEM) is a modern method for simulation. The idea is to utilize B-splines or NURBS basis functions for both computational domain descriptions and engineering computations. Re- fined isogeometric analysis (rIGA) employs a mixture of patches of elements with B-spline basis functions and C0 separators between them. This enables a reduction in the computational cost of direct solvers. Both IGA and rIGA come with challenging sparse matrix structures that are expensive to generate. In this paper, we show a hybrid parallelization method using hybrid-memory parallel machines. The two-level parallelization includes the partitioning of the computational mesh into sub-domains on the first level (MPI) and loop parallelization on the second level (OpenMP). We show that the hybrid paral- lelization of the integration reduces the contribution of this phase significantly. We compare the multi-frontal solver and alternating direction solver, including the integration and the factorization phases. [ABSTRACT FROM AUTHOR]