S3Guard

Mingliang Liu and Rajesh Balamohan explain why you shouldn’t use S3 as your primary Hadoop data store, as well as a tool which helps mitigate those problems:

Some of the real world use cases which can be impacted due to the S3 eventual consistency model are:

  1. Listing Files. Newly created files might not be visible for data processing. In Hive, Spark and MapReduce, this can lead to erroneous results from incomplete source data or failure to commit all intermediate results.

  2. ETL Workflow. Systems like Oozie rely on marker files to trigger the subsequent workflows. Any delay in the visibility of these files can lead to delays in the subsequent workflows.

  3. Existence-guarded path operations. Any action which fails if the destination path is present may see a deleted file in a listing, and so fail — even though the file has already been deleted.

Read on to see how S3Guard works and how to enable it in HDP 2.6.

Related Posts

Long-Term Storage In Kafka

Jay Kreps shows us that you can use Kafka as a primary data store: The short answer is that it’s not insane, people do this all the time, and Kafka was actually designed for this type of usage. But first, why might you want to do this? There are actually a number of use cases, […]

Read More

Creating A Simple Kafka Streams Application

Bill Bejeck has built a simple Kafka Streams application for us: This blog post will quickly get you off the ground and show you how Kafka Streams works. We’re going to make a toy application that takes incoming messages and upper-cases the text of those messages, effectively yelling at anyone who reads the message. This […]

Read More

Categories

June 2017
MTWTFSS
« May Jul »
 1234
567891011
12131415161718
19202122232425
2627282930