Exploiting task and data parallelism in ILUPACK’s preconditioned CG solver on NUMA architectures and many-core accelerators

Abstract

We present specialized implementations of the preconditioned iterative linear system solver in ILUPACK for Non-Uniform Memory Access (NUMA) platforms and many-core hardware co-processors based on the Intel Xeon Phi and graphics accelerators. For the conventional x86 architectures, our approach exploits task parallelism via the OmpSs runtime as well as a message-passing implementation based on MPI, respectively yielding a dynamic and static schedule of the work to the cores, with different numeric semantics to those of the sequential ILUPACK. For the graphics processor we exploit data parallelism by off-loading the computationally expensive kernels to the accelerator while keeping the numeric semantics of the sequential case.