Section: New Results

Direct solvers for sparse linear systems

In the context of the Mumps sparse direct solver (see Section  5.1 ), we worked in 2014 on: block-low-rank solvers and shared-memory parallelism [4] , [13] , hybrid (shared-distributed) parallelism and efficient collective communications in asynchronous environments [2] , and scheduling strategies to decrease the memory-usage of multifrontal solvers. Quite significant performance gains have been obtained on up to 2000 cores of a Bullx DLC system (CALMIP mesocentre), some of the corresponding developments will be made available in the next release of our solver. We also worked on setting up a consortium of industrial users to fund engineers working on MUMPS (see Section  7.1 ). These activities were done in collaboration with INP Toulouse and with CERFACS, CNRS, ENS Lyon, Univ. Bordeaux, EDF, LSTC (Livermore, California) and EMGS (Norway).