. (SISD, Single Instruction Single Data), . (SIMD, Single Instruction Multiple Data), , .
, , . .
, , , , () . , .
, . , . .
. . .
MPI : , :
, . - + ( MPI_Type_extent). . ( MPI_Type_size). .
MPI_Type_free . intMPI_Type_free(MPI_Datatype *datatype)
datatype .
MPI_Type_free MPI_DATATYPE_NULL. , .
.
int main(int argc,char **argv)
{
int size,rank,i,n=12;
float a[]={10.0,-1.0,2.0,3.0,7.0,6.0,3.0,1.0,-2.0,4.0,-9.0,20.0};
MPI_Status status;
MPI_Init(&argc,&argv);
MPI_Comm_rank(MPI_COMM_WORLD,&rank);
MPI_Comm_size(MPI_COMM_WORLD,&size);
float f=0,max=0,maxo=0;
int nachalo,konec,shag;
shag=n/(size-1);
if(rank!=size-1)
{
nachalo=rank*shag;
konec=rank*shag+shag;
max=a[nachalo];
for(i=nachalo;i<konec;i++)
|
|
|
if(a[i]>max)
max=a[i];
MPI_Send(&max,1,MPI_FLOAT,size-1,1,MPI_COMM_WORLD);
}
if(rank==size-1){
maxo=-32000;
for(i=0;i<size-1;i++)
{ MPI_Recv(&max,1,MPI_FLOAT,i,1,MPI_COMM_WORLD,&status);
if(maxo<max)
maxo=max; }
printf("%f\n",maxo);
}
MPI_Finalize();
}
NUMA.
NUMA (Non-Uniform Memory Access) , . , . , , NUMA- . , , API .
