Four Solutions to a Trivial Problem - Guy Steele Jr.

Google TechTalks · 36.4K views · 2016-01-28 · 1:01:47

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Overview

Guy Steele presents a small geometric problem and compares four computational approaches: a classic sequential solution and three parallel-friendly ones. Each is illustrated pictorially and with working code, weighing total work against time to solution.

On Hacker News

HN points to it as a clear lesson that algebraic properties like associativity unlock parallelism, applicable in any language.

Recommended by 4 HN people across 4 months · HN mentions 2017–2023

Topics

Algorithms & data structures Functional programming

What people said

tkf · 2020-10 · Strong recommendation
Hi, the author here. One of the hidden messages of the introduction is: watch Guy Steele's talks [1][2][3] if you are interested in data parallelism! These talks are not Julia-specific and the idea is applicable and very useful in any languages. My libraries are heavily inspired by these talks. Of course, if you haven't used Julia yet, it'd be great if (data) parallelism gives you an excuse to try it out! It has a fantastic foundation for composable multi-threaded parallelism [4]. [1] How to Think about Parallel Programming: Not! [LINK] [2] Four Solutions to a Trivial Problem [VIDEO] [3] Organizing Functional Code for Parallel Execution; or, foldl and foldr Considered Slightly Harmful [LINK] [4] Announcing composable multi-threaded parallelism in Julia [LINK]
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MathMonkeyMan · 2023-07 · Recommendation
Guy Steele Jr. worked on a language called "Fortress." There are a few good talks that he gives: - (toy problem) [VIDEO] - (parallelism) [LINK] - (languages) [LINK]
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heleninboodler · 2022-09 · Recommendation
This type of interviewing style is bullshit. It means the interviewer knows a better solution that is "clever" and expects you to either have the same cleverness epiphany on the spot or to have studied this question. Neither is actually very useful as a hiring criterion. Guy Steele gave an incredibly interesting guest talk[1] at google about four different ways to solve this exact problem, and the fact that it's an interesting enough topic for an hour long google talk should probably be a clue that you shouldn't be expected to invent the best solution on the whiteboard in 40 minutes. [1] [VIDEO]
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Sources

Video by Google TechTalks, played through YouTube.

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