An AWS spot instance helps to reduce the running cost of the EC2 instance. The user bids for a spot instance request specifying the maximum price that the user is willing to pay per hour per instance. Once the spot instance request is fulfilled, the instance will continue to run until it is manually terminated or the spot price increases above the maximum bid price. The user is not charged as per the max price; instead the user will be charged at the current spot price in that availability zone. To know the charges for spot instances, Amazon EC2 provides access to a data feed, which details the user’s spot instance usage and pricing every hour.
The present guide demonstrates how to subscribe or delete the spot instances price data feed.