Parallelism and Concurrency

A Sophomoric∗ Introduction to
Shared-Memory Parallelism and Concurrency
Dan Grossman
Version of February 23, 2012

Contents
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2

Meta-Introduction: An Instructor’s View of These Notes
1.1 Where This Material Fits in a Changing Curriculum . .
1.2 Six Theses On A Successful Approach to this Material
1.3 How to Use These Notes — And Improve Them . . . .
1.4 Acknowledgments . . . . . . . . . . . . . . . . . . .

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Introduction
2.1 More Than One Thing At Once . .
2.2 Parallelism vs. Concurrency . . .
2.3 Basic Threads and Shared Memory
2.4 Other Models . . . . . . . . . . .

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9

Basic Fork-Join Parallelism
3.1 A Simple Example: Okay Idea, Inferior Style
3.2 Why Not To Use One Thread Per Processor .
3.3 Divide-And-Conquer Parallelism . . . . . . .
3.4 The Java ForkJoin Framework . . . . . . . .
3.5 Reductions and Maps . . . . . . . . . . . . .
3.6 Data Structures Besides Arrays . . . . . . . .

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