/*
* Receive a block.
*/
void PackedData::recv(MPI::Intracomm& comm, int source)
{
MPI::Request request;
int myRank = comm.Get_rank();
int comm_size = comm.Get_size();
// Preconditons
if (source > comm_size - 1 || source < 0) {
UTIL_THROW("Source rank out of bounds");
}
if (source == myRank) {
UTIL_THROW("Source and desination identical");
}
request = comm.Irecv(begin_, capacity_, MPI::UNSIGNED_CHAR, source, 5);
request.Wait();
cursor_ = begin_;
}
/*
* Send a block.
*/
void PackedData::send(MPI::Intracomm& comm, int dest)
{
MPI::Request request;
int sendBytes = 0;
int comm_size = comm.Get_size();
int myRank = comm.Get_rank();
// Preconditions
if (dest > comm_size - 1 || dest < 0) {
UTIL_THROW("Destination rank out of bounds");
}
if (dest == myRank) {
UTIL_THROW("Source and desination identical");
}
sendBytes = cursor_ - begin_;
request = comm.Isend(begin_, sendBytes, MPI::UNSIGNED_CHAR, dest, 5);
request.Wait();
}
/*
* Receive a buffer.
*/
void Buffer::recv(MPI::Intracomm& comm, int source)
{
MPI::Request request;
int myRank = comm.Get_rank();
int comm_size = comm.Get_size();
// Preconditons
if (source > comm_size - 1 || source < 0) {
UTIL_THROW("Source rank out of bounds");
}
if (source == myRank) {
UTIL_THROW("Source and destination identical");
}
request = comm.Irecv(recvBufferBegin_, bufferCapacity_,
MPI::CHAR, source, 5);
request.Wait();
recvType_ = NONE;
recvPtr_ = recvBufferBegin_;
}
/*
* Send a buffer.
*/
void Buffer::send(MPI::Intracomm& comm, int dest)
{
MPI::Request request;
int sendBytes = 0;
int comm_size = comm.Get_size();
int myRank = comm.Get_rank();
// Preconditions
if (dest > comm_size - 1 || dest < 0) {
UTIL_THROW("Destination rank out of bounds");
}
if (dest == myRank) {
UTIL_THROW("Source and destination identical");
}
sendBytes = sendPtr_ - sendBufferBegin_;
request = comm.Isend(sendBufferBegin_, sendBytes, MPI::CHAR, dest, 5);
request.Wait();
// Update statistics.
if (sendBytes > maxSendLocal_) {
maxSendLocal_ = sendBytes;
}
}
int main(int argc, char *argv[]){
if(argc < 1)exit(1);
stringstream ss;
size_t size;
ss << argv[1]; ss >> size;
MPI::Init();
const int com_size = MPI::COMM_WORLD.Get_size(); // assume that com_size is a power of two
const int com_rank = MPI::COMM_WORLD.Get_rank();
const int com_last = com_size - 1;
int *m, *tmp;
m = new int[size];
tmp = new int[size];
size /= com_size;
// initialize ary with random numbers
srand((unsigned)time(NULL)+(unsigned)com_rank);
for(size_t i=0; i<size; i++)m[i] = rand();
// sort
for(int division_unit = com_size; division_unit > 1;){
int pivot;
for(int i=0;i<(int)sqrt(size);i++)tmp[i] = m[(int)((rand()/((double)RAND_MAX+1.0)) * size)];
sort(tmp, tmp + (int)sqrt(size));
pivot = tmp[(int)sqrt(size)/2];
if(com_rank%division_unit == 0){
for(int j = com_rank+1; j<com_rank+division_unit; j++)
MPI::COMM_WORLD.Send(&pivot, 1, MPI::INT, j, TAG_0);
}else{
MPI::COMM_WORLD.Recv(&pivot, 1, MPI::INT, (com_rank/division_unit)*division_unit, TAG_0);
}
division_unit /= 2;
int receive_datasize;
if((com_rank/division_unit)%2 == 0){
int *senddata = (int *)partition(m, m+size, bind2nd(less<int>(), pivot));
size_t rest_datasize = senddata - m;
size_t send_datasize = size - rest_datasize;
int send_to = com_rank+division_unit;
MPI::COMM_WORLD.Isend(&send_datasize, 1, MPI::INT, send_to, TAG_0);
MPI::Request req = MPI::COMM_WORLD.Isend(senddata, send_datasize, MPI::INT, send_to, TAG_1);
MPI::COMM_WORLD.Recv(&receive_datasize, 1, MPI::INT, send_to, TAG_0);
size = rest_datasize + receive_datasize;
MPI::COMM_WORLD.Recv(tmp, receive_datasize, MPI::INT, send_to, TAG_2);
req.Wait();
memcpy(m+rest_datasize, tmp, receive_datasize*sizeof(int));
}else{
int *senddata = (int *)partition(m, m+size, bind2nd(greater_equal<int>(), pivot));
size_t rest_datasize = senddata - m;
size_t send_datasize = size - rest_datasize;
int send_to = com_rank-division_unit;
MPI::COMM_WORLD.Isend(&send_datasize, 1, MPI::INT, send_to, TAG_0);
MPI::Request req = MPI::COMM_WORLD.Isend(senddata, send_datasize, MPI::INT, send_to, TAG_2);
MPI::COMM_WORLD.Recv(&receive_datasize, 1, MPI::INT, send_to, TAG_0);
size = rest_datasize + receive_datasize;
MPI::COMM_WORLD.Recv(tmp, receive_datasize, MPI::INT, send_to, TAG_1);
req.Wait();
memcpy(m+rest_datasize, tmp, receive_datasize*sizeof(int));
}
}
sort(m, m+size);
// print
int signal=0;
if(com_rank == 0){
for(size_t i=0; i<size; i++)cout << m[i] << endl;
// for(size_t i=0; i<m.size(); i++)cout << "[0]" << m[i] << endl;
if(com_rank != com_last)MPI::COMM_WORLD.Send(&signal, 1, MPI::INT, com_rank+1, TAG_0);
}else{
MPI::COMM_WORLD.Recv(&signal, 1, MPI::INT, com_rank-1, TAG_0);
for(size_t i=0; i<size; i++)cout << m[i] << endl;
// for(size_t i=0; i<m.size(); i++)cout << "[" << com_rank << "]" << m[i] << endl;
if(com_rank != com_last)MPI::COMM_WORLD.Send(&signal, 1, MPI::INT, com_rank+1, TAG_0);
}
MPI::Finalize();
delete [] m;
delete [] tmp;
}