1.第一个MPI程序
1 #include <mpi.h> 2 #include <stdio.h> 3 int main(int argc, char **argv) 4 { 5 //your code here 6 MPI_Init(&argc, &argv); 7 8 printf("Hello World! "); 9 10 MPI_Finalize(); 11 //end of your code 12 13 return 0; 14 }
2.获取进行数量
1 #include <stdio.h> 2 #include <mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int numprocs; 7 MPI_Init(&argc, &argv); 8 9 //your code here 10 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 11 //end of your code 12 13 printf("Hello World! The number of processes is %d ",numprocs); 14 15 MPI_Finalize(); 16 return 0; 17 }
3.获取进程ID
1 #include <stdio.h> 2 #include <mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int myid, numprocs; 7 MPI_Init(&argc, &argv); 8 9 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 10 11 //your code here 12 MPI_Comm_rank(MPI_COMM_WORLD, &myid); 13 //end of your code 14 15 printf("Hello World!I'm rank %d of %d ", myid, numprocs); 16 17 MPI_Finalize(); 18 return 0; 19 }
4.获取处理器名
1 #include <stdio.h> 2 #include <mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int len; 7 char name[MPI_MAX_PROCESSOR_NAME]; 8 MPI_Init(&argc, &argv); 9 10 //your code here 11 MPI_Get_processor_name (name, &len); 12 //end of your code 13 14 printf("Hello, world. I am %s. ", name); 15 16 MPI_Finalize(); 17 return 0; 18 }
5.运行时间
1 #include<stdio.h> 2 #include<mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int myid, numprocs; 7 double start, finish; 8 9 MPI_Init(&argc, &argv); 10 11 MPI_Comm_rank(MPI_COMM_WORLD, &myid); 12 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 13 14 //your code here 15 start = MPI_Wtime(); 16 17 printf("The precision is: %f ", MPI_Wtick()); 18 19 finish = MPI_Wtime(); 20 //your code here 21 22 printf("Hello World!I'm rank %d of %d, running %f seconds. ", myid, numprocs, finish-start); 23 24 MPI_Finalize(); 25 return 0; 26 }
6.同步
#include<stdio.h> #include<mpi.h> int main(int argc, char **argv) { int myid, numprocs; double start, finish; MPI_Init(&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, &myid); MPI_Comm_size(MPI_COMM_WORLD, &numprocs); //your code here MPI_Barrier(MPI_COMM_WORLD); //end of your code start = MPI_Wtime(); printf("The precision is: %f ", MPI_Wtick()); finish = MPI_Wtime(); printf("Hello World!I'm rank %d of %d, running %f seconds. ", myid, numprocs, finish-start); MPI_Finalize(); return 0; }
7.消息传递
int MPI_Send(void* msg_buf_p, int msg_size, MPI_Datatype msg_type, int dest, int tag, MPI_Comm communicator)
int MPI_Recv(void* msg_buf_p, int buf_size, MPI_Datatype msg_type, int source, int tag, MPI_Comm communicator， MPI_Status *status_p)
1 #include <stdio.h> 2 #include <mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int myid, numprocs, source; 7 MPI_Status status; 8 char message[100]; 9 10 MPI_Init(&argc, &argv); 11 MPI_Comm_rank(MPI_COMM_WORLD, &myid); 12 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 13 14 if(myid != 0) { 15 strcpy(message, "hello world!"); 16 17 //your code here 18 MPI_Send(message, strlen(message)+1, MPI_CHAR, 0, 99, MPI_COMM_WORLD); 19 //end of your code 20 } 21 else { //myid == 0 22 for(source=1; source<numprocs; source++) { 23 //your code here 24 MPI_Recv(message, 100, MPI_CHAR, source, 99, MPI_COMM_WORLD, &status); 25 //end of your code 26 27 printf("%s ", message); 28 } 29 } 30 31 MPI_Finalize(); 32 return 0; 33 }
8.地址偏移量
1 #include<stdio.h> 2 #include<mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int myid, numprocs; 7 MPI_Aint address1, address2, address3; 8 int a, b, c, dist1, dist2; 9 10 a = 1; 11 b = 2; 12 c = 3; 13 14 MPI_Init(&argc, &argv); 15 16 MPI_Comm_rank(MPI_COMM_WORLD, &myid); 17 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 18 19 20 // your code here 21 MPI_Address(&a, &address1); 22 MPI_Address(&b, &address2); 23 MPI_Address(&c, &address3); 24 // end of your code 25 26 dist1 = address2 - address1 ; 27 dist2 = address3 - address1 ; 28 29 if(myid == 0) { 30 printf("The distance between a and b is %d ", dist1); 31 printf("The distance between a and c is %d ", dist2); 32 } 33 34 MPI_Finalize(); 35 return 0; 36 }
9.数据的打包
int MPI_Pack(void* inbuf, int incount, MPI_datatype datatype, void *outbuf, int outcount, int *position, MPI_Comm comm) void* inbuf ： 输入缓冲区地址; int incount ：输入数据项数目; MPI_datatype datatype ：数据项的类型; void *outbuf ：输出缓冲区地址; int outcount ：输出缓冲区大小; int *position ：缓冲区当前位置; MPI_Comm comm ：通信子;
1 #include <stdio.h> 2 #include <mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int myid, numprocs, source; 7 MPI_Status status; 8 int i, j, position; 9 int k[2]; 10 int buf[1000]; 11 12 MPI_Init(&argc, &argv); 13 MPI_Comm_rank(MPI_COMM_WORLD, &myid); 14 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 15 16 i = 1; 17 j = 2; 18 19 if(myid == 0) { 20 21 position = 0 ; 22 23 // your code here 24 MPI_Pack(&i, 1, MPI_INT, buf, 1000, &position, MPI_COMM_WORLD); 25 MPI_Pack(&j, 1, MPI_INT, buf, 1000, &position, MPI_COMM_WORLD); 26 // end of your code 27 28 MPI_Send(buf, position, MPI_PACKED, 1, 99, MPI_COMM_WORLD); 29 } 30 else if (myid == 1){ 31 MPI_Recv(k, 2, MPI_INT, 0, 99, MPI_COMM_WORLD, &status); 32 33 position = 0 ; 34 35 MPI_Unpack(k, 2, &position, &i, 1, MPI_INT, MPI_COMM_WORLD); 36 MPI_Unpack(k, 2, &position, &j, 1, MPI_INT, MPI_COMM_WORLD); 37 38 printf("The number is %d and %d", i, j); 39 } 40 41 MPI_Finalize(); 42 return 0; 43 }
10.数据的解包
int MPI_Unpack(void* inbuf, int insize, int *position, void *outbuf, int outcount, MPI_Datatype datatype, MPI_Comm comm) void* inbuf ： 输入缓冲区地址; int insize ：输入数据项数目; MPI_datatype datatype ：数据项的类型; void *outbuf ：输出缓冲区地址; int outcount ：输出缓冲区大小; int *position ：缓冲区当前位置; MPI_Comm comm ：通信子;
1 #include <stdio.h> 2 #include <mpi.h> 3 4 int main(int argc, char **argv) 5 { 6 int myid, numprocs, source; 7 MPI_Status status; 8 int i, j, position; 9 int k[2]; 10 int buf[1000]; 11 12 MPI_Init(&argc, &argv); 13 MPI_Comm_rank(MPI_COMM_WORLD, &myid); 14 MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 15 16 i = 1; 17 j = 2; 18 19 if(myid == 0) { 20 21 position = 0 ; 22 23 MPI_Pack(&i, 1, MPI_INT, buf, 1000, &position, MPI_COMM_WORLD); 24 MPI_Pack(&j, 1, MPI_INT, buf, 1000, &position, MPI_COMM_WORLD); 25 26 MPI_Send(buf, position, MPI_PACKED, 1, 99, MPI_COMM_WORLD); 27 } 28 else if (myid == 1){ 29 MPI_Recv(k, 2, MPI_INT, 0, 99, MPI_COMM_WORLD, &status); 30 31 position = 0 ; 32 i = j = 0; 33 34 // your code here 35 MPI_Unpack(k, 2, &position, &i, 1, MPI_INT, MPI_COMM_WORLD); 36 MPI_Unpack(k, 2, &position, &j, 1, MPI_INT, MPI_COMM_WORLD); 37 // end of your code 38 39 printf("The number is %d and %d", i, j); 40 } 41 42 MPI_Finalize(); 43 return 0; 44 }
来自：MPI编程实训学习（超算习堂）