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Why Is This a Good Idea - Intro to Parallel Programming

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    Why is this transformation a good idea?
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    We still have to share the information
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    for a source object up here across all these threads.
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    That doesn't change from our previous implementation.
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    But now we don't have to share any destination object information at all,
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    because 1 thread is completely responsible for 1 destination object,
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    so we can load that object's information directly into that thread's local storage.
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    And we don't have to communicate between threads to sum up individual forces.
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    So it used to be we had P different threads here,
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    and we had to communicate between those P threads to add up all these forces.
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    Now because we only have 1 thread that's responsible for all these forces,
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    we don't have to do any communication between threads at all.
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    That thread can just accumulate all of the partial results in its local storage.
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    So the result is a faster implementation overall.
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    Dave discussed this technique generically in the last unit, Unit 5, and he used the term privatization.
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    So in making this transformation,
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    is the amount of parallelism now increased, decreased, or kept constant from the previous implementation?
Title:
Why Is This a Good Idea - Intro to Parallel Programming
Description:

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Video Language:
English
Team:
Udacity
Project:
CS344 - Intro to Parallel Programming
Duration:
01:00
Udacity Robot edited English subtitles for 08-12 Why Is This a Good Idea
Udacity Robot edited English subtitles for 08-12 Why Is This a Good Idea
Stacy Taylor approved English subtitles for 08-12 Why Is This a Good Idea
Lauren Birdsong edited English subtitles for 08-12 Why Is This a Good Idea
Cogi-Admin added a translation

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