Talk:MapReduce

message: Hello; I'm a new contributor; sorry for this comment's simplicity...  This article on (what I would have thought) an important topic is pretty bad; the C grade it's received reflects this.  It's also considered of "low-importance"; I have not yet located the project's importance scale, so I don't understand this.  MY QUESTION:  why is there no "needs work" indicator at the top of the article itself, like I see in so many others?  Readers should be warned.
DrTLesterThomas (talk) 15:01, 26 January 2014 (UTC)
thread_title:  Why no 'needs work' tag? 

message: Hi there,
I think a comparison with fork-join would be helpful. These two concepts seem similar, and pointing out both the similarities and differences would be helpful for the reader. There's an academic paper on the subject actually. Thank you. 205.175.116.125 (talk) 21:03, 18 March 2014 (UTC)
thread_title:  Comparison with fork-join 

message: I first heard about map-reduce frameworks in a lecture at Imperial College in 1994 given by Qian Wu.  [This paper] covers some of that work.  I wish I could find the lecture notes because they actually contained a diagram which was map-reduce.  I'm just putting this here for people looking for prior art against Google's patent.  Richard W.M. Jones (talk) 12:14, 3 May 2014 (UTC)
replies: text: Interesting pointer. However, note that map-reduce is not about map, or reduce IMHO. It's about optimizing the shuffle once, to get fail-safe recovery from machine loss for a whole class of programs. I don't know if fail-safety and recovery has been handled in this prior art? (As for map, and reduce, these have been common in functional programming anyway). Nevertheless, your source would make a good addition to the article to emphasize this point, that map-reduce is not about the map+reduce functions themselves, but about how to make this scale. --Chire (talk) 08:36, 5 May 2014 (UTC)
thread_title:  More prior art 

message: Does this reference support "MapReduce as a big data processing model is considered dead by many domain experts, as development has moved on to more capable and less disk-oriented mechanisms that incorporate full map and reduce capabilities."?
199.64.7.56 (talk) 06:11, 24 September 2015 (UTC)
replies: text: It is easy to find further references. E.g. Apache Mahout no longer accepts MapReduce contributions. "Exodus away from MapReduce" --Chire (talk) 09:29, 24 September 2015 (UTC)
replies: text:  Good find. Thank you. 199.64.7.58 (talk) 00:17, 25 September 2015 (UTC)
thread_title:  "MapReduce is dead" reference supportive of statement? 

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thread_title:  External links modified 

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thread_title:  External links modified 

message: FYI a new user has submitted an AfC for Draft:Reduce (algorithmics), since there's some overlap I thought I would mention it here. Rolf H Nelson (talk) 05:18, 4 May 2018 (UTC)
thread_title:  New draft article [[Reduce (algorithmics)]] 

message: I expect it to be "map reduce", "map-reduce", "map/reduce". Because without spaces, it is difficult to distinguish the programming model from the Hadoop MapReduce program.  — Preceding unsigned comment added by Sunapi386 (talk • contribs) 21:59, 8 January 2019 (UTC)
replies: text: Why are there no spaces in the Hadoop MapReduce program? The original Google paper that introduced/popularized MapReduce did not use spaces, but used the title "MapReduce". Therefore, this is the most appropriate name. The Hadoop name is dervied from this, not the other way round. HelpUsStopSpam (talk) 21:42, 10 January 2019 (UTC)
thread_title:  Why are there no spaces in the MapReduce programming model? 

message: I was trying to understand the examples on this page, in light of the type signatures given for Map and Reduce.  I was confused by the second example of averaging social network contacts, which said "The count info in the record is important if the processing is reduced more than one time".  Is this supposed to refer to calling Reduce more than once for the same key, and that it's essential to have Cnew in the output (Y,(A,Cnew)) as opposed to just outputting (Y,A) ?  If Reduce is called more than one time for the same key, then either Reduce needs to be able to fold its output with previous calls (which puts more rigid type constraints and invariants than the ones given in this article for Reduce), or MapReduce doesn't result in a finalized average.  Stackoverflow summary of the confusion here. Metaeducation (talk) 07:00, 9 October 2023 (UTC)
thread_title:  Reduce Called Multiple Times?