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 …

Dec 10, 2015 · mapreduce.reduce.shuffle.input.buffer.percent: How much of heap should be used for storing the map output, during the shuffle phase in the reducer. This setting determines the …

Aug 26, 2008 · MapReduce is a method to process vast sums of data in parallel without requiring the developer to write any code other than the mapper and reduce functions. The map function …

Jul 31, 2011 · For each input split a map task is spawned. So, over the lifetime of a mapreduce job the number of map tasks is equal to the number of input splits. mapred.map.tasks is just a …

Sep 12, 2012 · MapReduce is a framework originally developed at Google that allows for easy large scale distributed computing across a number of domains. Apache Hadoop is an open …

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 …

Jan 9, 2009 · What scenarios would warrant the use of the "Map and Reduce" algorithm? Is there a .NET implementation of this algorithm?

Sep 3, 2013 · What are the disadvantages of mapreduce? There are lots of advantages of mapreduce. But I would like to know the disadvantages of mapreduce too.

Mar 3, 2014 · Then, the MapReduce job stops at the map phase, and the map phase does not include any kind of sorting (so even the map phase is faster). Tom White has been an Apache …

Sep 25, 2013 · If you are using Hadoop Streaming, you can use the JobConf variables in a streaming job's mapper/reducer. As for the input file name of mapper, see the Configured …