Dear users,
I have a question about the correct use of the option
"PCFactorSetMatOrderingType" in PETSc.
I am solving a problem with 2.5M of unknowns distributed along 16
processors and I am using the block jacobi preconditioner and MPIAIJ
matrix format. I cannot figure out if the above option c
Edoardo:
You can test runtime option '-sub_pc_factor_mat_ordering_type' and use
'-log_view' to get performance on different orderings,
e.g.,petsc/src/ksp/ksp/examples/tutorials/ex2.c:
mpiexec -n 2 ./ex2 -ksp_view -sub_pc_type ilu -sub_pc_factor_mat_ordering_type
nd
I do not think the ordering i
Dear Hong and Matt,
thank you for your kind replay. I have just tested your suggestions and
applied " -sub_pc_type ilu -sub_pc_factor_mat_ordering_type nd/rcm" and, in
both cases, I have found a deterioration of performances with respect to
doing nothing (thus just putting default PCBJACOBI). Is
Edoardo:
Interesting. I thought it would not affect performance much. What happens if
you use -sub_pc_type lu'?
Hong
Dear Hong and Matt,
thank you for your kind replay. I have just tested your suggestions and applied
" -sub_pc_type ilu -sub_pc_factor_mat_ordering_type nd/rcm" and, in both cases