Analyzing AWS Spot Instance Pricing

Abstract

Many cloud computing vendors offer a preemptible class of service for rented virtual machines. In November 2017, Amazon.com changed the pricing mechanism for its preemptible "spot instances" so that prices would change more "smoothly." This paper analyzes the effect of this change on spot instance prices. It examines the prices immediately before and after the mechanism change to determine the extent to which prices themselves changed. It then compares the 90-day period immediately after the change in mechanism to the next 90-day period. Finally, it compares the two most recent 90-day periods (ending on October 15, 2018). Our results indicate that in addition to smoothing prices, the mechanism change introduced generally higher prices which is a trend that continues.