AWS provides a number of RI-specific cost management solutions out-of-the-box to help you better understand and manage your RIs. Using the RI Utilization and Coverage reports available in AWS Cost Explorer, you can visualize your RI data at an aggregate level or inspect a particular RI subscription. To access the most detailed RI information available, you can leverage the AWS Cost & Usage Report.
The Reserved Instance Utilization and Coverage reports are available out-of-the-box in AWS Cost Explorer. Using these reports, you can set custom RI utilization and coverage targets, and visualize how well you are tracking towards your goals. From there, you can refine the underlying data using the available filtering dimensions (e.g., account, instance type, scope, and others).
The RI Utilization report allows you to visualize your RI utilization (i.e., the percentage of purchased RI hours consumed by instances during a period of time), to identify and act upon opportunities to increase your RI usage efficiency (e.g., by modifying RI types or shifting workloads to match the constraints of active RIs).
The report shown below displays the increasingly cost-efficient daily utilization of c3.large RIs over a customer-defined time period.
The RI Coverage report allows you to discover how much of your overall instance usage is covered by RIs, so that you can make informed decisions about when to purchase or modify an RI to ensure maximum coverage. These reports visualize the percentage of running instance hours that are covered by RIs (i.e., RI coverage) in aggregate or in detail (e.g., by account, instance type, region, availability zone, tags, platform). In addition, they allow you to define an RI coverage threshold against which to monitor.
The report shown above displays an upward RI coverage trend of c3.large instances at a monthly level of detail.
One of the core benefits of the AWS Cost & Usage Report is the wealth of RI-related data that is made available to you. The AWS Cost & Usage Report can be customized to collect cost and usage data at the daily and monthly levels of detail, and is updated at least once per day. If desired, the AWS Cost & Usage Report can even be ingested directly into Amazon QuickSight or your Amazon Redshift cluster.
Leverage the most comprehensive AWS cost and usage dataset
The AWS Cost & Usage Report is your single location for accessing detailed information about your AWS costs and usage. Using this report, you can dig deeper into the specific AWS service, pricing, tagging, and other information as it applies to your RIs.
Access detailed reservation-related information
The AWS Cost & Usage Report contains a wealth of RI-related information, such as the the reservation ARN, the number of reservations, the total reserved units, and the number of units per reservation.
Calculate your RI savings using public on-demand rates
Each hourly line item of usage contains the discounted RI rate that was charged, as well as the public on-demand rate for that usage type at that time. You can quantify your savings by calculating the delta between the public on-demand rates and the rates you were charged.
Track the application of your RI discounts
Each line item of usage that receives an RI discount contains information about where the discount came from. This makes it easier to trace which instances are benefitting from specific reservations.
