Category Archives: YARN

Improvements in the Hadoop YARN Fair Scheduler

Categories: Hadoop MapReduce YARN

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.

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Apache Hadoop in 2013: The State of the Platform

Categories: Avro CDH Flume Hadoop HBase HDFS Hive Hue Impala Mahout MapReduce Oozie Pig Sqoop YARN ZooKeeper

For several good reasons, 2013 is a Happy New Year for Apache Hadoop enthusiasts.

In 2012, we saw continued progress on developing the next generation of the MapReduce processing framework (MRv2), work that will bear fruit this year. HDFS experienced major progress toward becoming a lights-out, fully enterprise-ready distributed filesystem with the addition of high availability features and increased performance. And a hint of the future of the Hadoop platform was provided with the Beta release of Cloudera Impala,

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MR2 and YARN Briefly Explained

Categories: MapReduce YARN

With CDH4 onward, the Apache Hadoop component introduced two new terms for Hadoop users to wonder about: MR2 and YARN. Unfortunately, these terms are mixed up so much that many people are confused about them. Do they mean the same thing, or not?

This post aims to clarify these two terms.

What is YARN?

YARN stands for “Yet-Another-Resource-Negotiator”. It is a new framework that facilitates writing arbitrary distributed processing frameworks and applications.

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