Sizing a Hadoop cluster is an important task as there are many factors influencing the performance. Capacity planning and the sizing of a Hadoop cluster are imperative for optimizing the distributed cluster environment with its related software. The number of machines, specifications of the machines, and effective process per node planning will allow you to optimize the performance effectively.

Within the Hadoop ecosystems, different layers (components/services) interact with each other, leading to performance overheads associated within a complex cluster stack between any of the layers; hence the need for requisite performance tests at each interface and appropriate tuning, as depicted in the following diagram:

There are many factors that influence the capacity planning, sizing, and performance of a complex Hadoop-distributed cluster. The following are a few factors for consideration: