Part Ill: Parallel Programming models The message-Passing model 1. Basic Concept: The message passing programming is the native model for MPP, Cow. The portability of programs is enchanced greatly by PVM and MPI libraries 2. Features Multiple threads: A message passing program uses either SPMD ( Single- Program-Multiple-Data)or MPMD (Multiple-Program-Multiple-Data Asynchronous operations at different nodes. Explicit synchronization: special synchronous operations(barrier, lock, critical region, event)are used Multiple address space: The processes of a parallel program reside in different address space Explicit data mapping and workload allocation Explicit communication: The processes interact by executing message passing operation NHPCC(Hefei)·USTC· CHINA glchenaustc edu.ciNHPCC(Hefei) •USTC •CHINA glchen@ustc.edu.cn The Message-Passing Model Part III:Parallel Programming Models 3 - 4