1.下载安装

1. 官网下载文件openmpi-3.1.2.tar.gz（也可以使用编译好的库，下载解压后直接从第五步开始配置环境变量https://download.csdn.net/download/kingskynine/10732466）。
2. 解压进入openmpi-3.1.2，./configure --help可以查看安装配置参数，这里直接./configure --prefix=/usr/local/openmpi-3.1.2,完成参数配置
3. 执行make完成编译
4. 执行make install 完成安装
5. 配置环境变量，执行vi /etc/profile打开配置文件，在最下面将mpi的lib库和bin库加入到系统变量里export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/openmpi-3.1.2/lib export PATH=$PATH:/usr/local/openmpi-3.1.2/bin，保存退出。
6. 执行source /etc/profile重新加载一下动态库
7. 执行mpirun,查看配置是否成功

2.测试demo

#include <stdio.h>
#include <string.h>
#include <time.h>
#include "mpi.h"

//cJsonPathName模拟输入文件
void master(int iTotalSlave,char *cJsonPathName)
{
	printf("start master\n");


	int i;
	printf("start send/\n");
	for (i = 1;i<=iTotalSlave;i++)
	{
		MPI_Send(&i, 1, MPI_INT,  i, 0, MPI_COMM_WORLD);
	}

	printf("start recv/\n");
	for (i = 1;i<=iTotalSlave;i++)
	{
		int nReturnNum;
		MPI_Status statusOrder;
		MPI_Recv(&nReturnNum, 1, MPI_INT, i, 0, MPI_COMM_WORLD, &statusOrder);
		printf("nReturnNum:%d\n",nReturnNum);
	}


}

void slave(int iID,int iTotalSlave)
{

	int nReceiveNum;
	MPI_Status statusOrder;
	MPI_Recv(&nReceiveNum, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, &statusOrder);
	printf("hello world node%d\n",nReceiveNum);

	nReceiveNum+=100;

	MPI_Send(&nReceiveNum, 1, MPI_INT,  0, 0, MPI_COMM_WORLD);

	return;
}

int main(int argc, char *argv[]) 
{

	if((argc == 2) && (0 == strcmp(argv[1], "-version")))
	{
		printf("version 2.0\n" );
		return 0;
	}
	else if(argc < 2)
	{
		printf("input param\n");
		return 1;
	}

	//	启动MPI
	MPI_Init(&argc, &argv);
	int iID,iTotalID;
	MPI_Comm_rank(MPI_COMM_WORLD, &iID);
	MPI_Comm_size(MPI_COMM_WORLD, &iTotalID);

	int iTotalSlave=iTotalID-1;
	(iID==0)?master(iTotalSlave,argv[1]):slave(iID, iTotalSlave);

	MPI_Finalize();
	return 0;
	
 }

3.makefile编写

LIBTOOL = libtool
CC      = $(LIBTOOL) --mode=compile --tag=CXX g++
LINK    = $(LIBTOOL) --mode=link --tag=CXX g++ -Wl,-rpath,./lib


INCS = -I/usr/local/openmpi-3.1.2/include

LIBS = -L/usr/local/openmpi-3.1.2/lib -lmpi

CFLAGS = -Wall -g -O2 -std=c++11  -fPIC -Wl,-rpath,./lib

CPPS	= $(wildcard ../src/*.cpp) 
OBJS	= $(patsubst %.cpp,%.lo,$(CPPS))
BIN	= mpitest 


all: $(BIN) 

$(OBJS):%.lo: %.cpp
	$(CC) -o $@ $(CFLAGS) $(INCS) -c $<

$(BIN): $(OBJS)
	$(LINK) -o $@ $(CFLAGS) $^ $(LIBS)

clean:
	$(LIBTOOL) --mode=clean --tag=CXX rm -f $(OBJS) $(BIN)

4.测试运行

[root@bogon Release]# mpirun --allow-run-as-root -n 4 mpitest 1
start master
start send/
start recv/
hello world node2
hello world node3
nReturnNum:101
nReturnNum:102
nReturnNum:103
hello world node1