Section: New Results

Optimizing NUMA effects in dense linear algebra software

Participants : Marc Baboulin, Adrien Rémy, Brigitte Rozoy, Masha Sosonkina.

We studied the impact of non-uniform memory accesses (NUMA) on the solution of dense general linear systems using an LU factorization algorithm. In particular we illustrated how an appropriate placement of the threads and memory on a NUMA architecture can improve the performance of the panel factorization and consequently accelerate the global LU factorization. We applied these placement strategies and presented performance results for a hybrid multicore/GPU LU algorithm as it is implemented in the public domain library MAGMA.