[petsc-users] direct solver for preconditioner

[hxie at umn.edu]

Hi,

Is the mumps the best option as a direct solver? Should the size of the 
linear system be less than 1d5 for mumps? Should I run the following to set 
mumps as the solver for the preconditioner?

mpirun -np 6 ~/bin/cats3d.1 -pc_type asm -ksp_type gmres -sub_ksp_type 
preonly -sub_pc_type lu -sub_pc_factor_mat_solver_package mumps

Bests,
Hui