![丐仂亢亠 仗仂舒 MPI-仗仂亞舒仄仄舒
#include <mpi.h>
#include <stdio.h>
int main( int argc, char *argv[] )
{
int rank, size;
MPI_Init( &argc, &argv );
MPI_Comm_rank( MPI_COMM_WORLD, &rank );
MPI_Comm_size( MPI_COMM_WORLD, &size );
printf( "I am %d of %dn", rank, size );
MPI_Finalize();
return 0;
}](https://image.slidesharecdn.com/20140420parallelprogrammingkalishenkolecture10-140421054423-phpapp02/85/20140420-parallel-programming_kalishenko_lecture10-7-320.jpg)
![亳仄亠 仗仂亠亶亠亶 仗亠亠仍从亳
#include <stdio.h>
#include <mpi.h>
main(int argc, char* argv[])
{
int rank;
MPI_Status st;
char buf[64];
MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
if(rank == 0) {
sprintf(buf, "Hello from processor 0");
MPI_Send(buf, 64, MPI_CHAR, 1, 0, MPI_COMM_WORLD);
} else {
MPI_Recv(buf, 64, MPI_CHAR, 0, 0, MPI_COMM_WORLD, &st);
printf("Process %d received %s n", rank, buf);
}
MPI_Finalize();
}](https://image.slidesharecdn.com/20140420parallelprogrammingkalishenkolecture10-140421054423-phpapp02/85/20140420-parallel-programming_kalishenko_lecture10-9-320.jpg)
![舒于亠亠仆亳亠:
int MPI_Wait (MPI_Request * request, MPI_Status * status)
int MPI_Test(MPI_Request *request, int *flag,
MPI_Status *status)
int MPI_Waitall(int count, MPI_Request array_of_requests[],
MPI_Status array_of_statuses[] )
int MPI_Waitany(int count, MPI_Request array_of_requests[],
int* index, MPI_Status *status )](https://image.slidesharecdn.com/20140420parallelprogrammingkalishenkolecture10-140421054423-phpapp02/85/20140420-parallel-programming_kalishenko_lecture10-17-320.jpg)
![亳仍亠仆亳亠 亳仍舒 Pi
#include "mpi.h"
#include <math.h>
int main(argc,argv)
int argc;
char *argv[];
{
int n, myid, numprocs, i;
double PI25DT = 3.141592653589793238462643;
double mypi, pi, h, sum, x, a;
MPI_Init(&argc,&argv);
MPI_Comm_size(MPI_COMM_WORLD,&numprocs);
MPI_Comm_rank(MPI_COMM_WORLD,&myid);](https://image.slidesharecdn.com/20140420parallelprogrammingkalishenkolecture10-140421054423-phpapp02/85/20140420-parallel-programming_kalishenko_lecture10-22-320.jpg)
![亠亠仗仂磲仂亳于舒仆亳亠 ( 于仂亰仄仂亢仆仄 亟舒仍亠仆亳亠仄) 仗仂亠仂于
于 亠于ﾑ亠亶 亞仗仗亠:
int MPI_Group_incl(MPI_Group* group, int n, int*
ranks, MPI_Group* newgroup)
group 亳仂亟仆舒 亞仗仗舒;
n 亳仍仂 仍亠仄亠仆仂于 于 仄舒亳于亠 ranks;
ranks 仄舒亳于 仆仂仄亠仂于 仗仂亠仂于, 亳亰 从仂仂
弍亟亠 仂亰亟舒仆舒 仆仂于舒 亞仗仗舒;
newgroup 从舒亰舒亠仍 仆舒 仂弍仍舒 亟仍 仂舒仆亠仆亳
亠亰仍舒舒 仂仗亠舒亳亳;
弌仂亰亟舒仆仆舒 亞仗仗舒 newgroup 仂亟亠亢亳 仍亠仄亠仆 亞仗仗
group, 仗亠亠亳仍亠仆仆亠 于 仄舒亳于亠 ranks: i-亶 仗仂亠
仂亰亟舒于舒亠仄仂亶 亞仗仗 newgroup 仂于仗舒亟舒亠 仗仂亠仂仄,
亳仄亠ﾑ亳仄 仆仂仄亠 ranks[i] 于 亞仗仗亠 group.](https://image.slidesharecdn.com/20140420parallelprogrammingkalishenkolecture10-140421054423-phpapp02/85/20140420-parallel-programming_kalishenko_lecture10-28-320.jpg)
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- 1. 亳弍仍亳仂亠从舒 MPI Message Passing Interface
- 2. 仂亳 MPI 弌舒仆亟舒 MPI 1.0 1995 亞仂亟, MPI 2.0 1998 亞仂亟. 仗亠亟亠仍磳 API (于舒亳舒仆 亟仍 弌亳, C++, Fortran, Java).
- 3. 束仂仄仗仍亠从 仗仂舒于从亳損 MPI 亳弍仍亳仂亠从舒. 弌亠亟于舒 从仂仄仗亳仍亳亳 亳 亰舒仗从舒 仗亳仍仂亢亠仆亳.
- 4. SPMD-仄仂亟亠仍. 0 1 2 3 舒亰仆亠 仗仂亠 于仗仂仍仆ﾑ 舒亰仆亠 舒亳 仂亟仆仂亞仂 亳 仂亞仂 亢亠 从仂亟舒.
- 5. 弌弍仂从舒 MPI-仗亳仍仂亢亠仆亳. 弌弍仂从舒 MPI-仗亳仍仂亢亠仆亳 仂亠于仍磳 仗仂仄仂 仗亠亳舒仍仆仂亶 亳仍亳. 仍舒亠 弌亳 mpicc. 亳仄亠: mpicc o mpihello mpihello.c 舒仗从 MPI-仗亳仍仂亢亠仆亳 仂亠于仍磳 仗仂仄仂 从仂仄舒仆亟 mpirun. mpirun np 4 mpihello
- 6. 个仆从亳亳 亳仆亳亳舒仍亳亰舒亳亳 亳 亰舒于亠亠仆亳 舒弍仂. int MPI_Init(int* argc,char*** argv) argc 从舒亰舒亠仍 仆舒 亠亳从 舒亞仄亠仆仂于 从仂仄舒仆亟仆仂亶 仂从亳 argv 从舒亰舒亠仍 仆舒 仗亳仂从 舒亞仄亠仆仂于 int MPI_Finalize()
- 7. 丐仂亢亠 仗仂舒 MPI-仗仂亞舒仄仄舒 #include <mpi.h> #include <stdio.h> int main( int argc, char *argv[] ) { int rank, size; MPI_Init( &argc, &argv ); MPI_Comm_rank( MPI_COMM_WORLD, &rank ); MPI_Comm_size( MPI_COMM_WORLD, &size ); printf( "I am %d of %dn", rank, size ); MPI_Finalize(); return 0; }
- 8. 个仆从亳亳 仂仗亠亟亠仍亠仆亳 舒仆亞舒 亳 亳仍舒 仗仂亠仂于. int MPI_Comm_size (MPI_Comm comm, int* size ) comm - 从仂仄仄仆亳从舒仂 size 亳仍仂 仗仂亠仂于 int MPI_Comm_rank(MPI_Comm comm, int* rank) comm 从仂仄仄仆亳从舒仂 rank 舒仆亞 仗仂亠舒
- 9. 亳仄亠 仗仂亠亶亠亶 仗亠亠仍从亳 #include <stdio.h> #include <mpi.h> main(int argc, char* argv[]) { int rank; MPI_Status st; char buf[64]; MPI_Init(&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, &rank); if(rank == 0) { sprintf(buf, "Hello from processor 0"); MPI_Send(buf, 64, MPI_CHAR, 1, 0, MPI_COMM_WORLD); } else { MPI_Recv(buf, 64, MPI_CHAR, 0, 0, MPI_COMM_WORLD, &st); printf("Process %d received %s n", rank, buf); } MPI_Finalize(); }
- 10. 个仆从亳亳 仂弍仄亠仆仂于 仂从舒-仂从舒 int MPI_Send( buf, count, datatype, dest, tag, comm ) void *buf; /* in */ int count, dest, tag; /* in */ MPI_Datatype datatype; /* in */ MPI_Comm comm; /* in */ buf - 舒亟亠 仆舒舒仍舒 弍亠舒 仗仂仍舒亠仄 亟舒仆仆 count - 亳仍仂 仗亠亠仍舒亠仄 仂弍亠从仂于 亳仗舒, 仂仂于亠于ﾑ亠亞仂 datatype dest - 仆仂仄亠 仗仂亠舒-仗亳亠仄仆亳从舒 tag - 仆亳从舒仍仆亶 亞, 亳亟亠仆亳亳亳ﾑ亳亶 仂仂弍亠仆亳亠 datatype - MPI-亳仗 仗亳仆亳仄舒亠仄 亟舒仆仆 comm - 从仂仄仄仆亳从舒仂
- 11. int MPI_Recv( buf, count, datatype, source, tag, comm, status ) void *buf; /* in */ int count, source, tag; /* in */ MPI_Datatype datatype; /* in */ MPI_Comm comm; /* in */ MPI_Status *status; /* out */ buf - 舒亟亠 弍亠舒 亟仍 仗亳亠仄舒 仂仂弍亠仆亳 count - 仄舒从亳仄舒仍仆仂亠 亳仍仂 仂弍亠从仂于 亳仗舒 datatype, 从仂仂仂亠 仄仂亢亠 弍 亰舒仗亳舒仆仂 于 弍亠 source - 仆仂仄亠 仗仂亠舒, 仂 从仂仂仂亞仂 仂亢亳亟舒亠 仂仂弍亠仆亳亠 tag - 仆亳从舒仍仆亶 亞, 亳亟亠仆亳亳亳ﾑ亳亶 仂仂弍亠仆亳亠 datatype - MPI-亳仗 仗亳仆亳仄舒亠仄 亟舒仆仆 comm - 从仂仄仄仆亳从舒仂 status - 舒 亰舒于亠亠仆亳
- 12. MPI-仗仂亞舒仄仄舒 亳仍亠仆仆仂亞仂 亳仆亠亞亳仂于舒仆亳 MPI_Init(&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, &r); MPI_Comm_size(MPI_COMM_WORLD, &p); if(r == 0) t = MPI_Wtime(); MPI_Barrier(MPI_COMM_WORLD); sum = 0.0; h = (b - a) / n; for(i = r; i < n; i += p) sum += f(a + (i + 0.5) * h); sum *= h; MPI_Send(&sum, 1, MPI_DOUBLE, 0, 0, MPI_COMM_WORLD); sum = 0;
- 13. MPI-仗仂亞舒仄仄舒 亳仍亠仆仆仂亞仂 亳仆亠亞亳仂于舒仆亳 if(r == 0) { double s; for(i = 0; i < p; i ++) { MPI_Recv(&s, 1, MPI_DOUBLE, i, 0, MPI_COMM_WORLD, &st); sum += s; } t = MPI_Wtime() - t; printf("Integral value = %lf. Time = %lf sec.n", sum, t); } MPI_Finalize(); }
- 14. 亳亟 仂亠仆 于亰舒亳仄仂亟亠亶于亳亶 MPI_Send 弍仍仂从亳ﾑ舒 仗亠亠仍从舒 仆从亳 于仂亰于舒舒亠 仗舒于仍亠仆亳亠 仂亞亟舒, 从仂亞亟舒 亳仂亟仆亶 弍亠 仄仂亢仆仂 仂于仂弍仂亢亟舒 (.亠. 亟舒仆仆亠 亳仍亳 从仂仗亳仂于舒仆 于 仗仂仄亠亢仂仆亶 亳仍亳 仂仗舒于仍亠仆) MPI_Bsend 弍亠亳亰仂于舒仆仆舒 仗亠亠仍从舒 仆从亳 于仂亰于舒舒亠 仗舒于仍亠仆亳亠 仂亞亟舒, 从仂亞亟舒 亟舒仆仆亠 从仂仗亳仂于舒仆 于 弍亠, 于亟亠仍磳仄亶 仗仂仍亰仂于舒亠仍亠仄
- 15. MPI_Ssend 亳仆仂仆仆舒 仗亠亠仍从舒 仆从亳 于仂亰于舒舒亠 仗舒于仍亠仆亳亠 仂亞亟舒, 从仂亞亟舒 仗仂亠-仗亳亠仄仆亳从 仗亠仗亳仍 从 于仗仂仍仆亠仆亳 仂仂于亠于ﾑ亠亶 仂仗亠舒亳亳 仗亳亠仄舒 MPI_Rsend 亳仆亠舒从亳于仆舒 仗亠亠仍从舒 仗仂于亠亟亠仆亳亠 仆从亳亳 仆亠 仂仗亠亟亠仍亠仆仂, 亠仍亳 仂仂于亠于ﾑ舒 仂仗亠舒亳 仗亳亠仄舒 仆亠 仆舒舒仍舒 于仗仂仍仆亠仆亳 (亟仍 于亠仍亳亠仆亳 仗仂亳亰于仂亟亳亠仍仆仂亳)
- 16. 亠弍仍仂从亳ﾑ亳亠 仗亠亠仍从亳 亠亟仆舒亰仆舒亠仆 亟仍 仗亠亠从亳 仂弍仄亠仆仂于 亳 于亳仍亠仆亳亶. 仗亠舒亳 舒亠仗仍磳 仆舒 亟于亠: 亳仆亳亳舒亳 亳 亰舒于亠亠仆亳亠.
- 17. 舒于亠亠仆亳亠: int MPI_Wait (MPI_Request * request, MPI_Status * status) int MPI_Test(MPI_Request *request, int *flag, MPI_Status *status) int MPI_Waitall(int count, MPI_Request array_of_requests[], MPI_Status array_of_statuses[] ) int MPI_Waitany(int count, MPI_Request array_of_requests[], int* index, MPI_Status *status )
- 19. int MPI_Bcast ( buffer, count, datatype, root, comm ) void* buffer - 仆舒舒仍仆亶 舒亟亠 弍亠舒 亟仍 仗亠亠亟舒亳 仂弍亠仆亳亶 int count - 亳仍仂 仗亠亠亟舒于舒亠仄 仍亠仄亠仆仂于 亟舒仆仆 MPI_Datatype datatype - 亳仗 仗亠亠亟舒于舒亠仄 亟舒仆仆 int root - 舒仆亞 仗仂亠舒, 仗仂仍舒ﾑ亠亞仂 亟舒仆仆亠 MPI_Comm comm - 从仂仄仄仆亳从舒仂
- 20. int MPI_Reduce ( sendbuf, recvbuf, count, datatype, op, root, comm ) void *sendbuf; 弍亠 仂仗亠舒仆亟仂于 void *recvbuf; 弍亠 仗亳亠仄舒 int count; 亳仍仂 亟舒仆仆 MPI_Datatype datatype; 亳仗 亟舒仆仆 MPI_Op op; 仂仗亠舒亳 int root; 舒仆亞 仗仂亠舒, 仂亟亠亢舒亠亞仂 亠亰仍舒 MPI_Comm comm; 从仂仄仄仆亳从舒仂 op
- 21. MPI_MAX 仄舒从亳仄仄 MPI_MIN 仄亳仆亳仄仄 MPI_SUM 仄仄舒 MPI_PROD 仗仂亳亰于亠亟亠仆亳亠 MPI_LAND 仍仂亞亳亠从仂亠 "亳" MPI_BAND 仗仂弍亳仂于仂亠 "亳" MPI_LOR 仍仂亞亳亠从仂亠 "亳仍亳" MPI_BOR 仗仂弍亳仂于仂亠 "亳仍亳" MPI_LXOR 仍仂亞亳亠从仂亠 亳从仍ﾑ舒ﾑ亠亠 "亳仍亳" MPI_BXOR 仗仂弍亳仂于仂亠 亳从仍ﾑ舒ﾑ亠亠 "亳仍亳"
- 22. 亳仍亠仆亳亠 亳仍舒 Pi #include "mpi.h" #include <math.h> int main(argc,argv) int argc; char *argv[]; { int n, myid, numprocs, i; double PI25DT = 3.141592653589793238462643; double mypi, pi, h, sum, x, a; MPI_Init(&argc,&argv); MPI_Comm_size(MPI_COMM_WORLD,&numprocs); MPI_Comm_rank(MPI_COMM_WORLD,&myid);
- 23. while (1) { if (myid == 0) { printf("Enter the number of intervals: (0 quits) "); scanf("%d",&n); } MPI_Bcast(&n, 1, MPI_INT, 0, MPI_COMM_WORLD); if (n == 0) break; h = 1.0 / (double) n; sum = 0.0; for (i = myid + 1; i <= n; i += numprocs) { x = h * ((double)i - 0.5); sum += 4.0 / (1.0 + x*x); } mypi = h * sum; MPI_Reduce(&mypi, &pi, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD); if (myid == 0) printf("pi is approximately %.16f, Error is %.16fn", pi, fabs(pi - PI25DT)); } MPI_Finalize();
- 24. 仆亠- 亳 亳仆舒- 从仂仄仄仆亳从舒仂 仆舒- 从仂仄仄仆亳从舒仂 仆亠- 从仂仄仄仆亳从舒仂 仆舒-从仂仄仄仆亳从舒仂 仂弍亠亟亳仆ﾑ 仗仂亠 亳亰 仂亟仆仂亶 亞仗仗. 仆亠-从仂仄仄仆亳从舒仂 仗仂亰于仂仍磳 仗亠亠亟舒于舒 亟舒仆仆亠 仄亠亢亟 仗仂亠舒仄亳 亳亰 舒亰仆 亳仆舒-从仂仄仄仆亳从舒仂仂于. 仆亠-从仂仄仄仆亳从舒仂 仆亠 仄仂亞 亳仗仂仍亰仂于舒 于 从仂仍仍亠从亳于仆 于亰舒亳仄仂亟亠亶于亳. 01 2 3 4 1 0 3 2 1 1
- 25. 舒亰仆舒亠仆亳亠 从仂仄仄仆亳从舒仂仂于 仂亟亟亠亢从舒 仗舒舒仍仍亠仍仆 弍亳弍仍亳仂亠从. 仂亟亟亠亢从舒 从仂仍仍亠从亳于仆 仂仗亠舒亳亶 仆舒 舒亳 于亳仍亳亠仍仆仂亞仂 仗仂舒仆于舒. 仂于亠仆亳亠 仂于仆 舒弍舒从亳亳 仗舒舒仍仍亠仍仆 仗亳仍仂亢亠仆亳亶.
- 26. 仆仂仄舒亳仂仆仆亠 仆从亳亳 亟仍 舒弍仂 亞仗仗舒仄亳 仗亠亟亠仍亠仆亳亠 舒亰仄亠舒 亞仗仗: int MPI_Group_size(MPI_Group group, int *size) group 亞仗仗舒; size 从舒亰舒亠仍 仆舒 仂弍仍舒 仗舒仄亳 亟仍 亰舒仗亳亳 亳仆仂仄舒亳亳 仂 从仂仍亳亠于亠 仗仂亠仂于 于 亞仗仗亠; 仗亠亟亠仍亠仆亳亠 仆仂仄亠舒 仗仂亠舒, 于仗仂仍仆ﾑ亠亞仂 于亰仂于 仆从亳亳, 于 亞仗仗亠: int MPI_Group_rank(MPI_Group group, int *rank) group 亞仗仗舒; rank 从舒亰舒亠仍 仆舒 仂弍仍舒 仗舒仄亳 亟仍 仂舒仆亠仆亳 仆仂仄亠舒 仗仂亠舒;
- 27. 舒亰仆仂 亟于 亞仗仗: int MPI_Group_difference(MPI_Group gr1, MPI_Group g2, MPI_Group* gr3) gr1 仗亠于舒 亞仗仗舒; gr2 于仂舒 亞仗仗舒; gr3 从舒亰舒亠仍 仆舒 仂弍仍舒 亟仍 仂舒仆亠仆亳 亠亰仍舒舒 仂仗亠舒亳亳; 仗仗舒 gr3 仂舒于仍亠仆舒 亳亰 仗仂亠仂于, 于仂亟亳 于 gr1, 仆仂 仆亠 于仂亟亳 于 gr2, 舒仗仂仍仂亢亠仆仆 于 仂仄 亢亠 仗仂磲从亠, 仂 亳 于 gr1.
- 28. 亠亠仗仂磲仂亳于舒仆亳亠 ( 于仂亰仄仂亢仆仄 亟舒仍亠仆亳亠仄) 仗仂亠仂于 于 亠于ﾑ亠亶 亞仗仗亠: int MPI_Group_incl(MPI_Group* group, int n, int* ranks, MPI_Group* newgroup) group 亳仂亟仆舒 亞仗仗舒; n 亳仍仂 仍亠仄亠仆仂于 于 仄舒亳于亠 ranks; ranks 仄舒亳于 仆仂仄亠仂于 仗仂亠仂于, 亳亰 从仂仂 弍亟亠 仂亰亟舒仆舒 仆仂于舒 亞仗仗舒; newgroup 从舒亰舒亠仍 仆舒 仂弍仍舒 亟仍 仂舒仆亠仆亳 亠亰仍舒舒 仂仗亠舒亳亳; 弌仂亰亟舒仆仆舒 亞仗仗舒 newgroup 仂亟亠亢亳 仍亠仄亠仆 亞仗仗 group, 仗亠亠亳仍亠仆仆亠 于 仄舒亳于亠 ranks: i-亶 仗仂亠 仂亰亟舒于舒亠仄仂亶 亞仗仗 newgroup 仂于仗舒亟舒亠 仗仂亠仂仄, 亳仄亠ﾑ亳仄 仆仂仄亠 ranks[i] 于 亞仗仗亠 group.
- 29. 弌亳亠仄舒 亳仗仂于 仂仂弍亠仆亳亶 MPI
- 30. 丐亳仗 于 MPI 乘 丐乘 MPI_CHAR MPI_SHORT MPI_INT MPI_LONG MPI_UNSIGNED_CHAR MPI_UNSIGNED_SHORT MPI_UNSIGNED MPI_UNSIGNED_LONG MPI_FLOAT MPI_DOUBLE MPI_LONG_DOUBLE 乘 丐乘 MPI_TYPE_CONTIGUOUS MPI_TYPE_VECTOR MPI_TYPE_HVECTOR MPI_TYPE_INDEXED MPI_TYPE_HINDEXED MPI_TYPE_STRUCT MPI_PACKED
- 31. 乘 丐乘 亳仗 MPI 亳仗 弌亳 MPI_CHAR signed char MPI_SHORT signed short int MPI_INT signed int MPI_LONG signed long int MPI_UNSIGNED_CHAR unsigned char MPI_UNSIGNED_SHORT unsigned short MPI_UNSIGNED unsigned int MPI_UNSIGNED_LONG unsigned long int MPI_FLOAT float MPI_DOUBLE double MPI_LONG_DOUBLE long double
- 32. 舒亰仆舒亠仆亳亠 仗仂亳亰于仂亟仆 亳仗仂于 仗亠亠仍从舒 亟舒仆仆, 舒仗仂仍仂亢亠仆仆 于 仆亠仄亠亢仆 仂弍仍舒 仗舒仄亳 于 仂亟仆仂仄 仂仂弍亠仆亳亳; 仗亠亠仍从舒 舒亰仆仂亳仗仆 亟舒仆仆 于 仂亟仆仂仄 仂仂弍亠仆亳亳; 仂弍仍亠亞亠仆亳亠 仗仂仆亳仄舒仆亳 仗仂亞舒仄仄;
- 33. 丱丐乘 丿 MPI-丱
- 34. 乘 丿 亳弍从亳 仗仂仍亠亟仂于舒亠仍仆 仗仂亞舒仄仄. 亳弍从亳 仆亠仂仂于亠于亳 亳仗仂于. 亳弍从亳 舒弍仂 MPI-仂弍亠从舒仄亳. 亰舒亳仄仆亠 弍仍仂从亳仂于从亳. 亠亟亠亠仄亳仆亳亰仄.
- 35. 亠亟亠亠仄亳仆亳亰仄 亰舒 亠 舒亰仆亳 于 仂仆仂亳亠仍仆 从仂仂 仗仂亠仂于 (race condition)
- 36. Deadlock if(rank == 0) { MPI_Ssend( 1 ) MPI_Recv(1) } else { MPI_Ssend( 0 ) MPI_Recv(0) }
- 37. 束亠亟亠亠仄亳仆亳仂于舒仆仆亶損 deadlock if(rank == 0) { MPI_Send( 1 ) MPI_Recv(1) } else { MPI_Send( 0 ) MPI_Recv(0) }