Shuffling and Sorting in Hadoop MapReduce
1. Objective In Hadoop, the process by which the intermediate output from mappers is transferred to the reducer is called Shuffling. Reducer gets 1 or more keys and associated values on the basis of...
1. Objective In Hadoop, the process by which the intermediate output from mappers is transferred to the reducer is called Shuffling. Reducer gets 1 or more keys and associated values on the basis of...
1. Hadoop Partitioner / MapReduce Partitioner In this MapReduce Tutorial, our objective is to discuss what is Hadoop Partitioner. The Partitioner in MapReduce controls the partitioning of the key of the intermediate mapper output. By...
1. Objective In this Hadoop MapReduce tutorial, we will provide you the detailed description of InputSplit in Hadoop. In this blog, we will try to answer What is Hadoop InputSplit, what is the need...
1. Hadoop RecordReader Tutorial – Objective In this Hadoop RecordReader Tutorial, We are going to discuss the important concept of Hadoop MapReduce i.e. RecordReader. The MapReduce RecordReader in Hadoop takes the byte-oriented view of...
1. Data Locality in Hadoop – Objective In Hadoop, Data locality is the process of moving the computation close to where the actual data resides on the node, instead of moving large data to...
1. Objective Hadoop InputFormat checks the Input-Specification of the job. InputFormat split the Input file into InputSplit and assign to individual Mapper. In this Hadoop InputFormat Tutorial, we will learn what is InputFormat in Hadoop...
1. Hadoop Combiner / MapReduce Combiner Hadoop Combiner is also known as “Mini-Reducer” that summarizes the Mapper output record with the same Key before passing to the Reducer. In this tutorial on MapReduce combiner...
1. Hadoop Mapper Tutorial – Objective Mapper task is the first phase of processing that processes each input record (from RecordReader) and generates an intermediate key-value pair. Hadoop Mapper store intermediate-output on the local...
1. Hadoop Reducer Tutorial – Objective In Hadoop, Reducer takes the output of the Mapper (intermediate key-value pair) process each of them to generate the output. The output of the reducer is the final...
1. Objective In this Big data Hadoop tutorial, we are going to learn Hadoop speculative execution. Apache Hadoop does not fix or diagnose slow-running tasks. Instead, it tries to detect when a task is...