Merge pull request #16 from L2Program/master

Master
CS-Swansea · Jul 8, 2016 · baf4243 · baf4243
2 parents ae03b76 + 428fcc1
commit baf4243
Showing 1 changed file with 61 additions and 93 deletions.
diff --git a/example-code/ompExample.cpp b/example-code/ompExample.cpp
@@ -30,97 +30,65 @@ SOFTWARE.
 // Example Usage: mpirun --pernode --hostfile [path] ./ompExample  //
 //-----------------------------------------------------------------//
 int main(int argc, char *argv []) {
-	MEL::Init(argc, argv);
-
-	// Who are we?
-	MEL::Comm comm = MEL::Comm::WORLD;
-	const int rank = MEL::CommRank(comm),
-			  size = MEL::CommSize(comm);
-
-	double start, end;
-
-	// Allocate buffers
-	const int LEN = 1e8;
-	int *src = MEL::MemAlloc<int>(LEN, 1), // Initilize to 1
-		*dst = (rank == 0) ? MEL::MemAlloc<int>(LEN) : nullptr;
-
-	// Perform the Reduction on 1 thread with MPI_SUM
-	start = MEL::Wtime();
-	MEL::Reduce(src, dst, LEN, MEL::Op::SUM, 0, comm); // Equivalent to standard MPI_Reduce call
-	end = MEL::Wtime();
-
-	if (rank == 0)
-		std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start) 
-		<< " seconds on 1 thread with MEL::Op::SUM == MPI_SUM." << std::endl;
-
-	// Create a MEL User Defined Operation using a functor wrapped in a map function
-	auto SUM = MEL::OpCreate<int, MEL::Functor::SUM>();
-
-	// Perform the Reduction on 1 thread
-	start = MEL::Wtime();
-	MEL::Reduce(src, dst, LEN, SUM, 0, comm);
-	end   = MEL::Wtime();
-
-	if (rank == 0) 
-		std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
-		<< " seconds on 1 thread with mapped MEL::FUNCTOR::SUM." << std::endl;
-
-	// Create a MEL User Defined Operation using a functor wrapped in a parallel map function
-	auto ompSUM = MEL::OMP::OpCreate<int, MEL::Functor::SUM>();
-
-	omp_set_num_threads(2);
-	omp_set_schedule(omp_sched_static, 0);
-
-	// Perform the Reduction on 4 threads
-	start = MEL::Wtime();
-	MEL::Reduce(src, dst, LEN, ompSUM, 0, comm);
-	end   = MEL::Wtime();
-
-	if (rank == 0)
-		std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
-		<< " seconds on 2 threads with parallel mapped MEL::FUNCTOR::SUM." << std::endl;
-
-	omp_set_num_threads(4);
-	omp_set_schedule(omp_sched_static, 0);
-
-	// Perform the Reduction on 8 threads
-	start = MEL::Wtime();
-	MEL::Reduce(src, dst, LEN, ompSUM, 0, comm);
-	end = MEL::Wtime();
-
-	if (rank == 0)
-		std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
-		<< " seconds on 4 threads with parallel mapped MEL::FUNCTOR::SUM." << std::endl;
-
-	omp_set_num_threads(8);
-	omp_set_schedule(omp_sched_static, 0);
-
-	// Perform the Reduction on 8 threads
-	start = MEL::Wtime();
-	MEL::Reduce(src, dst, LEN, ompSUM, 0, comm);
-	end = MEL::Wtime();
-
-	if (rank == 0)
-		std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
-		<< " seconds on 8 threads with parallel mapped MEL::FUNCTOR::SUM." << std::endl;
-
-	omp_set_num_threads(16);
-	omp_set_schedule(omp_sched_static, 0);
-
-	// Perform the Reduction on 16 threads
-	start = MEL::Wtime();
-	MEL::Reduce(src, dst, LEN, ompSUM, 0, comm);
-	end = MEL::Wtime();
-
-	if (rank == 0)
-		std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
-		<< " seconds on 16 threads with parallel mapped MEL::FUNCTOR::SUM." << std::endl;
-
-	// Clean up the operations when we are done with them
-	MEL::OpFree(SUM, ompSUM);
-	// Clean up buffers
-	MEL::MemFree(src, dst);
-
-	MEL::Finalize();
-	return 0;
+    MEL::Init(argc, argv);
+
+    // Who are we?
+    MEL::Comm comm = MEL::Comm::WORLD;
+    const int rank = MEL::CommRank(comm),
+              size = MEL::CommSize(comm);
+
+    double start, end;
+
+    // Allocate buffers
+    const int LEN = 1e8;
+    int *src = MEL::MemAlloc<int>(LEN, 1), // Initilize to 1
+        *dst = (rank == 0) ? MEL::MemAlloc<int>(LEN) : nullptr;
+
+    // Perform the Reduction on 1 thread with MPI_SUM
+    start = MEL::Wtime();
+    //MPI_Reduce(src, dst, LEN, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
+    MEL::Reduce(src, dst, LEN, MEL::Op::SUM, 0, comm); 
+    end = MEL::Wtime();
+
+    if (rank == 0)
+        std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start) 
+        << " seconds on 1 thread with MEL::Op::SUM == MPI_SUM." << std::endl;
+
+    // Create a MEL User Defined Operation using a functor wrapped in a map function
+    auto SUM = MEL::OpCreate<int, MEL::Functor::SUM>();
+
+    // Perform the Reduction on 1 thread
+    start = MEL::Wtime();
+    MEL::Reduce(src, dst, LEN, SUM, 0, comm);
+    end   = MEL::Wtime();
+
+    if (rank == 0) 
+        std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
+        << " seconds on 1 thread with mapped MEL::FUNCTOR::SUM." << std::endl;
+
+    // Create a MEL User Defined Operation using a functor wrapped in a parallel map function
+    auto ompSUM = MEL::OMP::OpCreate<int, MEL::Functor::SUM>();
+
+    // For 2, 4, 8, 16 threads
+    for (int n = 2; n <= 16; n <<= 1) {
+        omp_set_num_threads(n);
+        omp_set_schedule(omp_sched_static, 0);
+
+        // Perform the Reduction on n threads
+        start = MEL::Wtime();
+        MEL::Reduce(src, dst, LEN, ompSUM, 0, comm);
+        end   = MEL::Wtime();
+
+        if (rank == 0)
+            std::cout << "Reduced " << LEN << " elements in " << std::setw(10) << (end - start)
+            << " seconds on " << n << " threads with parallel mapped MEL::FUNCTOR::SUM." << std::endl;
+    }
+
+    // Clean up the operations when we are done with them
+    MEL::OpFree(SUM, ompSUM);
+    // Clean up buffers
+    MEL::MemFree(src, dst);
+
+    MEL::Finalize();
+    return 0;
 }