In Apache Hadoop 2, YARN and MapReduce 2 (MR2) are long-needed upgrades for scheduling, resource management, and execution in Hadoop. At their core, the improvements separate cluster resource management capabilities from MapReduce-specific logic. They enable Hadoop to share resources dynamically between MapReduce and other parallel processing frameworks, such as Cloudera Impala; allow more sensible and finer-grained resource configuration for better cluster utilization; and permit Hadoop to scale to accommodate more and larger jobs.
In this installment of “Meet the Project Founder,” we speak with Josh Wills (@josh_wills), Cloudera’s Senior Director of Data Science and founder of Apache Crunch and Cloudera ML.
What led you to your project idea(s)?
When I first started at Cloudera in 2011, I had a fairly vague job description, no real responsibilities, and wasn’t all that familiar with the Apache Hadoop stack, so I started working on various pet projects in order to learn more about the tools and the use cases in domains like healthcare and energy.
One of the common questions I get from students and developers in my classes relates to IDEs and MapReduce: How do you create a MapReduce project in Eclipse and then debug it?
To answer that question, I have created a screencast showing you how, using Cloudera’s QuickStart VM. The QuickStart VM helps developers get started writing MapReduce code without having to worry about software installs and configuration. Everything is installed and ready to go.
For those of you attending this week’s StampedeCon event in St. Louis, I’d encourage you to check out the “Thinking in MapReduce” session presented by Cerner’s Ryan Brush. The session will cover the value that MapReduce and Apache Hadoop offer to the healthcare space, and provide tips on how to effectively use Hadoop ecosystem tools to solve healthcare problems.
Big Data challenges within the healthcare space stem from the standard practice of storing data in many siloed systems.
Starting in CDH 4.2, YARN/MapReduce 2 (MR2) includes an even more powerful Fair Scheduler. In addition to doing nearly all that it could do in MapReduce 1 (MR1), the YARN Fair Scheduler can schedule non-MapReduce jobs, schedule based on fine-grained memory instead of slots, and support hierarchical queues. In this post, you’ll learn what the Fair Scheduler’s role is and how it fulfills it, what it means to be a YARN “scheduler,” and dive into its new features and how to get them running on your cluster.