| The Message Passing Interface (MPI) is widely used for solving significant scientific and engineering problems on parallel computers. User Datagram Protocol (UDP) is defined to transfer messages among interconnected computers. This thesis demonstrated that it is possible to implement a shared memory on a distributed memory machine, using MPI and UDP as communication methods.; We implemented two NSM (Network Shared Memory) libraries that simulate a shared memory in a distributed memory environment. These two libraries used MPI and UDP as communication methods, respectively. The performances of the NSM libraries and the direct MPI and UDP were compared by using a real application, the TSP problem, as well as a group of simulating experiments on a distributed memory platform and a shared memory platform. Two more applications, the merge sort algorithm and the Back-Propagation Neural Network, were used to compare the NSM libraries on the distributed memory platform.; Our experimental results show that MPI outperforms UDP as the communication protocol from several aspects on both platforms. |
