Dear Professor,
I have a question about the bjacobi+ilu, I'm in the place
src/ksp/ksp/tutorials
and running the ex2 with
mpirun -np 40 -bind-to core ./ex2 -m 2000 -n 2000 -ksp_max_it 1000000 -ksp_rtol 1e-10 -ksp_type gmres -pc_type bjacobi -sub_pc_type ilu -sub_pc_factor_levels 10 -ksp_monitor_short
on the Intel machine with 40 cores, the petsc is complied with MKL and ICC/MPIICC with O3.
I found the numerical results are not the same from time to time, although they all right, the iterations are not exactly the same from time to time. Where have I done wrong?
Humm, iterations should rarely change. You can see floating point scale differences. Try jacobi instead of ilu and/or try not using MKL.
I'm looking forward to hear you!
Best,
Gang Chen
Sichuan Univertsity,
School of Mathematics,
Chengdu, China