Hadoop Interview questions

Total available count: 27
Subject - Apache
Subsubject - Hadoop

What is a BlockManager?

A key-value store for blocks that acts as a cache is Block Manager. It runs on every node, i.e. an executor and a driver, in a Spark runtime environment. It provides interfaces for putting and retrieving blocks both locally and remotely into various stores, i.e. memory, disk, and off-heap. The storage for most of the data in Spark is managed by a BlockManager, i.e. block that represents a cached RDD partition, broadcast data, and intermediate shuffle data.

Next 5 interview question(s)

What is Speculative Execution of a tasks?
What is Task, with regards to Spark Job execution?
What is DAGSchedular and how it performs?
Please define executors in detail?
Please explain, how workers work, when a new Job submitted to them?