
How does the MapReduce sort algorithm work? - Stack Overflow
MapReduce's use of input files and lack of schema support prevents the performance improvements enabled by common database system features such as B-trees and hash partitioning, though …
c# - Map and Reduce in .NET - Stack Overflow
What scenarios would warrant the use of the "Map and Reduce" algorithm? Is there a .NET implementation of this algorithm?
Get names of all keys in the collection - Stack Overflow
I know this is an old thread, but I seem to have a similar need. I'm using the nodejs mongodb native driver. The resulting temporary collection seems to empty always. I'm using the mapreduce function …
mapreduce - What is Hive: Return Code 2 from …
I am getting: FAILED: Execution Error, return code 2 from org.apache.hadoop.hive.ql.exec.MapRedTask While trying to make a copy of a partitioned table using the commands in the hive console: CREATE
NoClassDefFoundError for simple Yarn application - Stack Overflow
May 4, 2014 · The issue will happen on YARN clusters where the ResourceManager and/or NodeManager daemons are started with an application classpath that is incomplete. Even something …
mapreduce - How does Hadoop perform input splits? - Stack Overflow
5 Difference between block size and input split size. Input Split is logical split of your data, basically used during data processing in MapReduce program or other processing techniques. Input Split size is …
Can you explain when and why mapreduce is invoked in hive
Jun 18, 2015 · Can you explain when and why mapreduce is invoked in hive Asked 10 years, 5 months ago Modified 7 years, 6 months ago Viewed 16k times
mapreduce - How to optimize shuffling/sorting phase in a hadoop job ...
Dec 10, 2015 · mapreduce.shuffle.max.threads: Number of worker threads for copying the map outputs to reducers. mapreduce.reduce.shuffle.input.buffer.percent: How much of heap should be used for …
java - Mapreduce Combiner - Stack Overflow
I have a simple mapreduce code with mapper, reducer and combiner. The output from mapper is passed to combiner. But to the reducer, instead of output from combiner,output from mapper is passed. Ki...
mapreduce - Hadoop one Map and multiple Reduce - Stack Overflow
Also your use of MapReduce paradigm for the given problem is incorrect, using a single map function and multiple "different" reduce function makes no sense, it shows that you are just using map to pass …