Mpich2: problems with communications
I'm using mpich2 1.0.7. I installed and configured it on 2 machines, started daemons.
The problems begin when I launch my program: first MPI_Bcast succeeds, but the second one (or any other communication function) hangs. Source code is attached.
Also when I call MPI_Bcast, second machine deamon prints the following:
F9Virtual64_mpdman_1 (run282): invalid msg from lhs; expecting ringsize got: {}
Can anyone look at the code and tell me what's wrong?
Code:
#include <mpi.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <sys/time.h>
int main(int arg_c, char** arg_v)
{
if(arg_c<2)
{
printf("Input file not specified\n");
return 0;
}
if(MPI_Init(&arg_c, &arg_v)!=MPI_SUCCESS)
{
printf("MPI initialization failed\n");
return 0;
}
int ProcNum, ProcRank;
MPI_Comm_size(MPI_COMM_WORLD, &ProcNum);
MPI_Comm_rank(MPI_COMM_WORLD, &ProcRank);
int size;
double e;
double* A;
double* b;
double* x, *xprev;
FILE* f=0;
if(!ProcRank)
{
f=fopen(arg_v[1], "r");
if(!f)
{
printf("Error opening input file\n");
MPI_Finalize();
return 0;
}
fscanf(f, "%d", &size);
printf("Enter desired accuracy\n");
scanf("%lf", &e);
}
if(!ProcRank)
printf("Broadcasting matrix size\n");
if(MPI_Bcast(&size, 1, MPI_INT, 0, MPI_COMM_WORLD)!=MPI_SUCCESS)
if(!ProcRank)
printf("Failed to broadcast matrix size\n");
if(!ProcRank)
printf("Broadcasting accuracy\n");
if(MPI_Bcast(&e, 1, MPI_DOUBLE, 0, MPI_COMM_WORLD)!=MPI_SUCCESS)
if(!ProcRank)
printf("Failed to broadcast accuracy\n");
A=new double[size*size];
b=new double[size];
x=new double[size];
xprev=new double[size];
memset(x, 0, size*sizeof(double));
memset(xprev, 0, size*sizeof(double));
if(!ProcRank)
{
for(int i=0; i<size; i++)
for(int j=0; j<size; j++)
fscanf(f, "%lf", &(A[i*size+j]));
for(int i=0; i<size; i++)
fscanf(f, "%lf", &(b[i]));
fclose(f);
}
if(!ProcRank)
printf("Waiting all processes to be initialized\n");
MPI_Barrier(MPI_COMM_WORLD);
if(!ProcRank)
printf("Broadcasting matrix\n");
MPI_Bcast(A, size*size, MPI_DOUBLE, 0, MPI_COMM_WORLD);
if(!ProcRank)
printf("Broadcasting b\n");
MPI_Bcast(b, size, MPI_DOUBLE, 0, MPI_COMM_WORLD);
double cursum, totalsum;
int fin, itercount=0;
if(!ProcRank)
printf("Starting calculation\n");
struct timeval tv1, tv2;
gettimeofday(&tv1, 0);
do
{
MPI_Bcast(xprev, size, MPI_DOUBLE, 0, MPI_COMM_WORLD);
itercount++;
for(int i=0; i<size; i++)
{
int snum=(size)/ProcNum;
cursum=0.0;
totalsum=0.0;
for(int n=ProcRank*snum; n<((ProcRank==ProcNum-1)?(size):((ProcRank+1)*snum)); n++)
{
if(n<=i-1)
cursum+=A[i*size+n]*x[n];
else
cursum+=A[i*size+n]*xprev[n];
}
MPI_Barrier(MPI_COMM_WORLD);
MPI_Reduce(&cursum, &totalsum, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
if(!ProcRank)
{
x[i]=xprev[i]-1.0/A[i*size+i]*(totalsum-b[i]);
}
}
if(!ProcRank)
{
fin=1;
for(int i=0; i<size; i++)
if(fabs(x[i]-xprev[i])>e)
fin=0;
if(!fin)
memcpy(xprev, x, size*sizeof(double));
}
MPI_Bcast(&fin, 1, MPI_INT, 0, MPI_COMM_WORLD);
}
while(!fin);
gettimeofday(&tv2, 0);
if(!ProcRank)
{
printf("Matrix A:\n");
for(int i=0; i<size; i++)
{
for(int j=0; j<size; j++)
printf("%lf ", A[i*size+j]);
printf("\n");
}
printf("\n");
printf("Line b:\n");
for(int i=0; i<size; i++)
printf("%lf ", b[i]);
printf("\n");
printf("Iteration number: %d\n", itercount);
printf("Calculation time: %d microseconds\n", (tv2.tv_sec-tv1.tv_sec)*1000000+(tv2.tv_usec-tv1.tv_usec));
printf("Results: \n");
for(int i=0; i<size; i++)
printf("x%d=%lf\n", i+1, x[i]);
}
MPI_Barrier(MPI_COMM_WORLD);
delete [] A;
delete [] b;
delete [] x;
delete [] xprev;
MPI_Finalize();
return 0;
}
