The Gaia AVU-GSR parallel solver: Preliminary studies of a LSQR-based application in perspective of exascale systems

Valentina Cesare, Ugo Becciani, Alberto Vecchiato, Mario Gilberto Lattanzi, Fabio Pitari, Mario Raciti, Giuseppe Tudisco, Marco Aldinucci, Beatrice Bucciarelli

Abstract: Highlights•Customized implementation of preconditioned LSQR algorithm.•Optimized solving of large and sparse systems with peculiar sparsity schemes.•GPU parallelization to gain in performance compared to CPU parallelization.•Optimized data copies host-to-device and device-to-host.•Parallelization with OpenACC in perspective of exascale systems.