int main()
{
int ndims=2;
int gdims[2]={31,777602};
int num_io_procs=24;
bool converged=false;
long int start[ndims], kount[ndims];
int iorank, numaiotasks;
long int tpsize;
long int psize;
long int pgdims;
int scnt;
pgdims=1;
for(int i=0;i<ndims;i++)
pgdims*=gdims[i];
tpsize = 0;
numaiotasks = 0;
while (! converged){
for(iorank=0;iorank<num_io_procs;iorank++){
numaiotasks = CalcStartandCount(PIO_DOUBLE,ndims,gdims,num_io_procs, iorank, start,kount);
if(iorank<numaiotasks)
printf("iorank %d start %ld %ld count %ld %ld\n",iorank,start[0],start[1],kount[0],kount[1]);
if(numaiotasks<0) return numaiotasks;
psize=1;
scnt=0;
for(int i=0;i<ndims;i++){
psize*=kount[i];
scnt+=kount[i];
}
tpsize+=psize;
}
if(tpsize==pgdims)
converged = true;
else{
printf("Failed to converge %ld %ld %d\n",tpsize,pgdims,num_io_procs);
tpsize=0;
num_io_procs--;
}
}
}
int PIOc_InitDecomp(const int iosysid, const int basetype,const int ndims, const int dims[],
const int maplen, const PIO_Offset *compmap, int *ioidp,const int *rearranger,
const PIO_Offset *iostart,const PIO_Offset *iocount)
{
iosystem_desc_t *ios;
io_desc_t *iodesc;
int mpierr;
int ierr;
int iosize;
int ndisp;
for(int i=0;i<ndims;i++){
if(dims[i]<=0){
piodie("Invalid dims argument",__FILE__,__LINE__);
}
}
ios = pio_get_iosystem_from_id(iosysid);
if(ios == NULL)
return PIO_EBADID;
if(PIO_Save_Decomps){
char filename[30];
if(ios->num_comptasks < 100) {
sprintf(filename, "piodecomp%2.2dtasks%2.2ddims%2.2d.dat",ios->num_comptasks,ndims,counter);
}else if(ios->num_comptasks < 10000) {
sprintf(filename, "piodecomp%4.4dtasks%2.2ddims%2.2d.dat",ios->num_comptasks,ndims,counter);
}else{
sprintf(filename, "piodecomp%6.6dtasks%2.2ddims%2.2d.dat",ios->num_comptasks,ndims,counter);
}
PIOc_writemap(filename,ndims,dims,maplen,compmap,ios->comp_comm);
counter++;
}
iodesc = malloc_iodesc(basetype, ndims);
if(rearranger == NULL)
iodesc->rearranger = ios->default_rearranger;
else
iodesc->rearranger = *rearranger;
if(iodesc->rearranger==PIO_REARR_SUBSET){
if((iostart != NULL) && (iocount != NULL)){
fprintf(stderr,"%s %s\n","Iostart and iocount arguments to PIOc_InitDecomp",
"are incompatable with subset rearrange method and will be ignored");
}
iodesc->num_aiotasks = ios->num_iotasks;
ierr = subset_rearrange_create( *ios, maplen, compmap, dims, ndims, iodesc);
}else{
if(ios->ioproc){
// Unless the user specifies the start and count for each IO task compute it.
if((iostart != NULL) && (iocount != NULL)){
// printf("iocount[0] = %ld %ld\n",iocount[0], iocount);
iodesc->maxiobuflen=1;
for(int i=0;i<ndims;i++){
iodesc->firstregion->start[i] = iostart[i];
iodesc->firstregion->count[i] = iocount[i];
compute_maxIObuffersize(ios->io_comm, iodesc);
}
iodesc->num_aiotasks = ios->num_iotasks;
}else{
iodesc->num_aiotasks = CalcStartandCount(basetype, ndims, dims,
ios->num_iotasks, ios->io_rank,
iodesc->firstregion->start, iodesc->firstregion->count);
}
compute_maxIObuffersize(ios->io_comm, iodesc);
}
// Depending on array size and io-blocksize the actual number of io tasks used may vary
CheckMPIReturn(MPI_Bcast(&(iodesc->num_aiotasks), 1, MPI_INT, ios->ioroot,
ios->my_comm),__FILE__,__LINE__);
// Compute the communications pattern for this decomposition
if(iodesc->rearranger==PIO_REARR_BOX){
ierr = box_rearrange_create( *ios, maplen, compmap, dims, ndims, iodesc);
}
/*
if(ios->ioproc){
io_region *ioregion = iodesc->firstregion;
while(ioregion != NULL){
for(int i=0;i<ndims;i++)
printf("%s %d i %d dim %d start %ld count %ld\n",__FILE__,__LINE__,i,dims[i],ioregion->start[i],ioregion->count[i]);
ioregion = ioregion->next;
}
}
*/
}
*ioidp = pio_add_to_iodesc_list(iodesc);
performance_tune_rearranger(*ios, iodesc);
return PIO_NOERR;
}
