package mpi.threads ;

import mpi.*;
import java.util.Arrays;

public class MultiplexNoComm {
	
  int DATA_SIZE= 512*1024 ;	
  int REPEAT = 200 ; 
  
  public MultiplexNoComm () {
  }
  
  public MultiplexNoComm (String args[]) throws Exception {

    MPI.Init(args);

    long start, stop, time; 

    int me = MPI.COMM_WORLD.Rank() ;
    int size = MPI.COMM_WORLD.Size() ; 
      
    int intArray [] = new int[DATA_SIZE];
    int intArray2 [] = new int[DATA_SIZE];

    int intReadArray [] = new int[DATA_SIZE];
    int intReadArray2 [] = new int[DATA_SIZE];
		
    for(int i =0 ; i<DATA_SIZE ; i++) {
      intArray[i] =  (i+1) + 1000 ;
      intArray2[i] = (i+1) + 2000 ;
    }    	
		
    if(me == 0) { 
      int tag = 1000 ; 		
      
      start = System.nanoTime() ; 
 
      //omp parallel for default(shared) schedule(static,1) 
      for(int peer = 1 ; peer< size ; peer++) { 
        for(int j=0 ; j<REPEAT ; j++) { 	      
          MPI.COMM_WORLD.Send(intArray,0,DATA_SIZE,MPI.INT,peer,tag);
	}
      }

      stop = System.nanoTime(); 

      time = stop - start ; 
      System.out.println("==="); 
      System.out.println("time ="+(time/(1000*1000*1000))+" seconds"); 
      System.out.println("==="); 

    } else { 
	    
      int tag = 1000 ;  		
      for(int k=0 ; k<DATA_SIZE ; k++) { 		 
        intReadArray[k] = 0; 
      }
      
      for(int j=0 ; j<REPEAT ; j++) { 
        MPI.COMM_WORLD.Recv(intReadArray,0,DATA_SIZE,MPI.INT,0,tag);
	
	if(Arrays.equals(intArray, intReadArray)) {
	  //System.out.println(" Thread A passed "); 	    
	}
	else {
          System.out.println(" Process <"+me+" failed "); 		    
	}
      }


    }
       	
    MPI.COMM_WORLD.Barrier();

    if(MPI.COMM_WORLD.Rank() == 0) {
      System.out.println("MultiplexNoComm TEST Completed");	
    }

    MPI.Finalize();

  } 
    
  public static void main(String args[]) throws Exception{
    MultiplexNoComm test = new MultiplexNoComm(args);
  }

}