Solving-Poisson-Equation

2-D Poisson equation problem is solved by central finite difference five directories

1. Serial solver

compile command:

g++ poisson.cpp main.cpp -o run

run command:

./run

2. OpenMP solver

compile command:

g++ poisson.cpp main.cpp -o run -fopenmp 

run command:

./run

3. MPI solver

compile command:

mpicxx poisson.cpp main.cpp -o run 

run command:

mpirun -n 12 ./run

4. Kokkos solver

Make sure the system supports C++17.
after config the kokkos on ThetaGPU, make in the local directory:

make -j KOKKOS_DEVICES=OpenMP

OR:

make -j KOKKOS_DEVICES=Cuda 

to choose OpenMP or Cuda.
run command:

./run.host

OR:

./run.cuda

5. MPI+Kokkos solver

qsub -I -n 4 -t 60 -q default --attrs filesystems=home,grand -A IMEXLBM

export OMPI_CXX=/grand/IMEXLBM/czhao/Kokkos/kokkos/bin/nvcc_wrapper

export OMP_PROC_BIND=spread

export OMP_PLACES=threads

make in the local directory:

make -j

module load PrgEnv-gnu/8.3.3 
cudatoolkit-standalone/11.6.2
make KOKKOS_CXX_STANDARD=c++17

run command: if you want to use n cpu + n gpu

mpirun -hostfile $COBALT_NODEFILE -n num -npernode 8 LBM.exe