An Evaluation of the Discount Rates for Spot Instances on Amazon EC2

Abstract

This study analyzes and evaluates the discount rates for Spot Instances employed using the new Spot pricing model on Amazon EC2. Spot Instances are virtual computational resources provided as physical computers. The pricing model of Spot Instances changes prices frequently. In 2017, Amazon EC2 dramatically changed its Spot pricing model (Nov-2017 model). This update reduced sudden spikes, seasonal components, and trends. The Nov-2017 model provides Spot Instances at low and predictable prices while adjusting gradually based on long-term trends in supply and demand, saving consumers up to 90% off the On-Demand Instance prices. For the Nov-2017 model’s minimum discount rates, mean discount rates, and fluctuation ranges of discount rates from the On-Demand prices are evaluated. The results show that distribution registering 70% to 90% is the most frequent, which is more than half the Spot Instances.