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Map Reduce: A simple introduction (2010)

ksat.me Books & learning Tutorials & guides Computer science Candidate

Resurfaced independently across 4 calendar years, with breakout response in 2 of them.

submissions
4
submitters
4
observed span
2010–2015
peak thread · 36 comments
117 pts
latest 20+ return · 2014-05-02
117 pts

Submission timeline

2007–2026

One slot for every year since HN launched. Height is that year's peak points; orange marks a 100+ point or 50+ comment breakout. Select a bar to open its strongest thread.

First comments on top threads

HN comment order

Map Reduce seems very interesting, but every example I have seen explains it in terms of counting frequency of words in documents. I would love to have someone explain it with an actual business example. I can't think of many real world uses where counting the frequency of words would matter to most businesses. (besides maybe some analysis of log files)

briffle·117-point thread·

"If homicide, suicide or resigining the job is not an option, how would you solve it?" I would create an n-ary tree (n is arbitrary, maybe 100) from coworkers. The 'leafs' would produce an array of ten numbers based on the blogs assigned to them. Then each node in the tree would take n arrays and sum them up into one array, until me, the root have the final array of ten numbers. First: this is much simpler than what…

nadam·100-point thread·

The first top-level comment from each of the four biggest threads, in HN’s own order. Excerpts are shortened; open a comment for full context.

Breakout years
2

100+ points or 50+ comments

Total points
221

reference only — not used in Hall rules or ranking

Total comments
52

reference only — not used in Hall rules or ranking

Every submission

DateTitle as submittedByPointsComments
2010-09-30Map Reduce: A really simple introductionFirst breakoutguffshemr10016
2012-06-18Simple introduction to MapReduceninetax30
2014-05-02Map Reduce: A simple introduction (2010)Best thread · Latest 20+ point returnawjr11736
2015-02-08MapReduce: a really simple introductionpajtai10