MapReduce Execution in Hadoop

In this article we have tried to summaries,  how a MapReduce program executes in Hadoop environment.

 

MapReduce 1 Execution Sequence:

MapReduce execution starts with below command.

Hadoop Vs Relational Database Management System

Hadoop or RDBMS? There are a lot of different opinions out there among these two technologies. Few people think Hadoop is a replacement of RDBMS, few say Hadoop is the future, and few thinks Hadoop have just got hype. So I have tried to find out what is the reality what Hadoop is really meant for.

HDFS Architecture

The Hadoop Distributed File System (HDFS) is a highly fault tolerant file system designed and optimized to be deployed on a distributed infrastructure established with a bunch commodity hardware. HDFS provides high throughput access to application data and is best suited for applications that have large data sets.

Discovery of Hadoop

Back in the early 2000’s Dough Cutting was attempting to build an Open Source Search engine called Nutch. They were facing trouble managing their distributed system even when they were running on very few computers. Nutch was stuck with its two half time developers.