README.md

P3-miniapps

P3-miniapps are designed to evalute Performance, Portability and Productivity (P3) of mini-applications with C++ parallel algorithms (stdpar). We have implemented 3D heat equation solver and 4D (2D space and 2D velocity space) Vlasov-Poisson solver. These mini-apps are parallelized with MPI + "X" programming model in C++. "X" includes stdpar, OpenMP, OpenACC, OpenMP4.5, Kokkos, Thrust, CUDA, and HIP. As well as the language standard parallelization (stdpar), we also focus on the language standard high dimensional array support mdspan.

This repository includes the following mini-apps:

• heat3d
• heat3d_mpi
• vlp4d
• vlp4d_mpi

For questions or comments, please find us in the AUTHORS file.

Usage

Preparation

Firstly, you need to git clone on your environment as

git clone --recursive https://github.com/yasahi-hpc/P3-miniapps.git

This software relies on external libraries including Kokkos, mdspan and fftw. Kokkos and mdspan are included as submodules. CUDA-Aware-MPI or ROCm-Aware-MPI are also needed for Nvidia and AMD GPUs. In the following, we assume that fftw and MPI libraries are appropriately installed.

Compile

We rely on CMake to build the applications. 4 mini applications heat3d, heat3d_mpi, vlp4d, and vlp4d_mpi are provided. You will compile with the following CMake command. For -DAPPLICATION option, <app_name> should be choosen from the application names provided above. To enable test, you should set -DBUILD_TESTING=ON. Following table summarizes the allowed combinations of <programming_model>, <compiler_name>, and <backend> for each DEVICE.

cmake -DCMAKE_CXX_COMPILER=<compiler_name> \
      -DCMAKE_BUILD_TYPE=<build_type> \
      -DBUILD_TESTING=OFF \
      -DPROGRAMMING_MODEL=<programming_model> \
      -DBACKEND=<backend> \
      -DAPPLICATION=<app_name> 

DEVICE	programming_model	compiler_name	backend
IceLake	OPENMP THRUST KOKKOS STDPAR	icpc g++ icpc nvc++	OPENMP
P100 V100 A100	CUDA OPENMP OPENACC THRUST KOKKOS STDPAR	g++ nvc++ nvc++ g++ nvcc_wrapper nvc++	CUDA
MI100	HIP OPENMP THRUST KOKKOS	hipcc hipcc hipcc hipcc	HIP

• For Nvidia Devices, you need to add -DCMAKE_CUDA_ARCHITECTURES=<device> (device=60, 70, 80 for P100, V100 and A100, respetively) to compile for <programmind_model>=[THRUST, CUDA]. For <programmind_model>=KOKKOS and <backend>=CUDA, one further needs to add Kokkos options for installation like

-DKokkos_ENABLE_CUDA=On \
-DKokkos_ENABLE_CUDA_LAMBDA=On \
-DKokkos_ARCH_AMPERE80=On

• For AMD Devices, you also need to pass -DCMAKE_HIP_ARCHITECTURES=<device> (device=gfx908 for MI100) to compile for <programming_model>=OPENMP and <backend>=HIP. For <programmind_model>=KOKKOS and <backend>=HIP, one further needs to add Kokkos options for installation like

-DKokkos_ENABLE_HIP=On \
-DKokkos_ARCH_VEGA908=On

Run

To run the applications, several command line arguments are necessary. Following table summarizes the list of commad line arguments for each mini-app.

app_name	Arguments	Examples
heat3d	nx, ny, nz, nbiter, freq_diag	heat3d --nx 512 --ny 512 --nz 512 --nbiter 1000 --freq_diag 0
heat3d_mpi	px, py, pz, nx, ny, nz, nbiter, freq_diag	heat3d_mpi --px 2 --py 2 --pz 2 --nx 256 --ny 256 --nz 256 --nbiter 1000 --freq_diag 0
vlp4d	(file_name)	vlp4d SLD10_large.dat
vlp4d_mpi	f	vlp4d_mpi -f SLD10.dat

For the Kokkos version, you additionally need to give "num_threads", "teams", "device", "num_gpus", and "device_map", e.g. vlp4d_mpi --num_threads 1 --teams 1 --device 0 --num_gpus 8 --device_map 1 -f SLD10.dat.

More details are given in the docs for heat3d and vlp4d.

Citations

@INPROCEEDINGS{Asahi2021, 
      author={Asahi, Yuuichi and Latu, Guillaume and Bigot, Julien and Grandgirard, Virginie},
      booktitle={2021 International Workshop on Performance, Portability and Productivity in HPC (P3HPC)},
      title={Optimization strategy for a performance portable Vlasov code},
      year={2021},
      volume={},
      number={},
      pages={79-91},
      doi={10.1109/P3HPC54578.2021.00011}}

@INPROCEEDINGS{Asahi2019,
    author = {Asahi, Yuuichi and Latu, Guillaume and Grandgirard, Virginie and Bigot, Julien}, 
    title = {Performance Portable Implementation of a Kinetic Plasma Simulation Mini-App}, 
    booktitle = {Accelerator Programming Using Directives}, 
    year = {2020},
    editor = {Wienke, Sandra and Bhalachandra, Sridutt}, 
    series = {series},
    pages = {117--139},
    address = {Cham},
    publisher = {Springer International Publishing}, 
}