mpi - How to improve this programme to work master also -


in mpi programme works slave nodes. how modify work master also. because working of master improve performance of system.

int a,b,c, slaveid,recvid,root, rank,size;  mpi_init(&argc, &argv);  mpi_comm_rank(mpi_comm_world, &rank); mpi_comm_size(mpi_comm_world, &size);  /*-------------------------- master ------------------------------*/  if(rank == 0){      n =10;        for(slaveid=1; slaveid<size; slaveid++){         mpi_send(&n, 1, mpi_int, slaveid, 1, mpi_comm_world);     }      for(recvid=1; recvid<size; recvid++){         mpi_recv(&a, 1, mpi_int, recvid, 2, mpi_comm_world, &status);      printf(" id = %d , send = %d\n",recvid,a);     } }  /*-------------------------- slave ------------------------------*/  if(rank>0){      mpi_recv(&b, 1, mpi_int, 0, 1, mpi_comm_world, &status);      c = b*3;      mpi_send(&c, 1, mpi_int, 0, 2, mpi_comm_world);  }  mpi_finalize();

}

within block delimited 

if(rank == 0){  }

insert, @ appropriate location, line

work_like_a_slave(argument1, argument2,...)

the appropriate location between loop sends messages , loop receives messages master isn't entirely idle while slaves toil.

whether has measurable impact on performance depends on number of factors question doesn't provide enough information on base guess; factors such as: how many slaves there , therefore how busy master sending , receiving messages, how work each process compared messaging does, etc.

be prepared, if numbers work against you, measurable impact negative, pressing master service slow down computation.


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