4. Parallel Computing 14. Introduction

14.7  Control-Parallel Machines

We saw earlier how data-parallel machines rely on multiple processors conducting

similar operations on each of a large set of data. In  control-parallel machines, there are

multiple instruction streams and no common control. Thus these machines are also often

called MIMD ("Multiple-Instruction, Multiple-Data") machines. Within this category,

there are two predominant organizations:

Shared memory

Distributed memory

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Parallel Computing

Shared Memory Multiprocessors

In a shared memory machine, all processors conceptually share a common memory. Each

processor is executing its own instruction stream. The processors can communicate with

one another based on inspection and modification of data common to both of them.

Processor

Processor

Processor

Processor

Memory

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