fe-demo-cpp

A minimal matrix-free finite element (FEM) demo in C++ for solving the 1D Poisson equation using:

• MPI domain decomposition
• Conjugate Gradient (CG) solver
• Matrix-free operator
• Optional CUDA acceleration

Requirements

• C++17 compiler
• CMake ≥ 3.20
• MPI (OpenMPI / MPICH)

Optional:

• NVIDIA CUDA toolkit

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Build and Run (MPI CPU)

cmake -S . -B build-mpi -DCMAKE_BUILD_TYPE=Debug -DMINIFEM_ENABLE_MPI=ON
cmake --build build-mpi -j
mpiexec -n 4 ./build-mpi/poisson1D_mpi

Build and Run (MPI CUDA)

cmake -S . -B build-gpu -DCMAKE_BUILD_TYPE=Release -DMINIFEM_ENABLE_MPI=ON -DMINIFEM_ENABLE_CUDA=ON
cmake --build build-gpu -j
CUDA_LAUNCH_BLOCKING=1 mpiexec -n 4 ./build-gpu/poisson1D_mpi_cuda