from:https://developer.nvidia.com/mvapich
MVAPICH2 is an open source implementation of Message Passing Interface (MPI) that delivers the best performance, scalability and fault tolerance for high-end computing systems and servers using InfiniBand, 10GigE/iWARP and RoCE networking technologies. MVAPICH2 simplifies the task of porting MPI applications to run on clusters with NVIDIA GPUs by supporting standard MPI calls from GPU device memory. It optimizes the data movement between host and GPU, and between GPUs in the best way possible while requiring minimal or no effort from the application developer.
MVAPICH2是一个开源的MPI系统，其对使用InfiniBand（无线带宽技术）的高端计算系统和服务器提供高性能、可适应性、容错性，是一种具有10GigE/iWARP速度，RoCE网络的技术。
MVAPICH2简化MPI应用程序移植到与NVIDIA GPU集群上运行，并支持标准的MPI调用GPU设备内存的任务。它以最佳方式优化了主机和GPU之间、GPU和GPU之间的数据移动，而应用程序开发人员角度只需付出很少的努力，甚至不需要。 MVAPICH2以为使用Infiniband，10GigE/iWARP，ROCE网络的高性能集群提供优秀的可扩展性和容错著称。
Key Features:
- High performance RDMA-based inter-node MPI point-to-point communication from/to GPU device memory (GPU-GPU, GPU-Host and Host-GPU)
- High performance intra-node MPI point-to-point communication for multi-GPU adapters/node (GPU-GPU, GPU-Host and Host-GPU)
- Optimized and tuned MPI collective communication from/to GPU device memory
- MPI Datatype support in point-to-point and collective communication from/to GPU device memory
- Taking advantage of CUDA IPC (available in CUDA 4.1) in intra-node communication for multiple GPU adapters/node
- Efficient synchronization mechanism using CUDA Events for pipelined data transfers from/to GPU device memory
主要特点：
- 高性能的基于RDMA的节点间的MPI点至点通信（GPU-GPU，GPU-Host，Host-GPU）
- 高性能节点内的MPI点至点的多GPU通信（GPU-GPU，GPU-Host,Host-GPU）
- 优化和调整 GPU设备内存的MPI集体通信
- MPI的数据类型的支持GPU设备内存的点至点和集体通信
- 节点多GPU卡内通信使用了CUDA IPC（CUDA4.1 支持 IPC）
- 使用CUDA事件为流水线数据的内存数据GPU传输的高效同步机制
Performance:
The latest performance results using MVAPICH2 for MPI communication from/to/between GPU devices can be found on the OSU Microbenchmark Page for GPUs
Availability:
The latest version of MVAPICH2 can be downloaded from: http://mvapich.cse.ohio-state.edu/download/mvapich2/ NVIDIA GPU related features are available in MVAPICH2 releases starting from 1.8.
MVAPICH Project Page:
http://mvapich.cse.ohio-state.edu/overview/mvapich2/features.shtml