Hello, call MatMatMult(S,G,MAT_INITIAL_MATRIX,PETSC_DEFAULT_DOUBLE_PRECISION,J,ierr);CHKERRQ(ierr)
I use this operation to compute matrix-matrix product. It's correct, but quite slow. For instance, my matrix S is a dense matrix size of <6x762048 complex double> and matrix G is a sparse matrix with 2 nonzeros per row and size of <762048x254016 complex double> Time spent on S*G was ~22 secs with 32 processes over 4 nodes. There is infiniband between nodes. Is it a real life or I'm doing something wrong? Regards, Alexander
