CSC/ECE 506 Fall 2007/wiki1 6 r8e

Communication Architecture Background

Parallel computers must have two types of architectures. One of these is this computer architecture, or that of the individual processors that are interconnected. Each processor has an instruction set architecture and microarchitecture, or a system of computer organization at a very low level that make of the computer architecture. The second type of architecture that is needed for parallel computing is that of a commuincation architecture, or a way in which the individual processors can communicate and work together to do useful things, this includes synchronization among the processors.

Three Parallel Programming Models

Many parallel programming models exist, however the most common are described below.

Shared Address Space

Shared address space programming can be understood best when related to a message or bulletin board. Anyone can post a message on this board, and anyone can read what others have written. The key to the shared address space model is the fact that all of the vital information is posted in shared locations that can be accessed by all.

Message Passing

Message passing machines convey information in a way similar to that of a phone call or a letter. There are very specific events that trigger the movement of information from a unique sender to a unique receiver.

Data Parallel

Data parallel programming is by far the most regulated of the three parallel programming models. In this type of programming work is carried out on different elements of a data set by different operators. Once all operations are finished information is exchanged among all, basically after the work is done a "global reorganization of data" is carried out.