Added OMP functor benchmark example

example-code/ompExample.cpp

@@ -0,0 +1,126 @@
+/*
+The MIT License(MIT)
+
+Copyright(c) 2016 Joss Whittle
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files(the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions :
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+#define  MEL_IMPLEMENTATION
+#include "MEL_omp.hpp"
+
+#include <iomanip>
+
+//-----------------------------------------------------------------//
+// 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;
+}