After purchasing a reserved instance, check its details, such as matching instances and its normalization factor, to ensure compatibility. Assess its performance by reviewing the bill details, utilization, and coverage.
View deductible instances
After purchasing a reserved instance, use the deduction prediction feature to identify which of your pay-as-you-go instances it can match.
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In the upper-right corner of the Reserved Instance list, click Check Deductible Reserved Instances.
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Select the region/zone where the reserved instance is located.
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Find the reserved instance and click View Deductible Instances on the right side of the list.
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This prediction is for reference only. The final bill reflects the actual deduction.
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If a pay-as-you-go instance is created by E-MapReduce (EMR), Container Service for Kubernetes (ACK), or Elastic Container Instance (ECI), the deduction prediction feature cannot display the instance. However, this does not affect the actual deduction.
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View normalization factor
The normalization factor represents the computing power of an instance and usually depends on the number of vCPUs. Computing power of a reserved instance = Normalization factor of the instance type × Number of instances in the reserved instance.
Understanding the computing power of a reserved instance helps you with the following:
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When you split or merge reserved instances, you must ensure that the total computing power remains the same.
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When you use a regional reserved instance to cover pay-as-you-go instances of different sizes, it helps you assess the usage of the reserved instance.
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In the upper-right corner of the Reserved Instance list, click View Normalization Factors.
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Filter by instance family to view the normalization factor for each instance type.
You can also click Download to save the normalization factor table to your computer for offline viewing.
View usage details
View the bill details of a reserved instance to see how it offsets costs for your pay-as-you-go instances.
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In the Actions column of the reserved instance list, click View Bills.
NoteYou can also click View Usage Details in the upper-right corner of the reserved instance list to view the deduction details for all reserved instances in the current region.
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On the Usage Details tab, view the deduction details for the current reserved instance, such as the deduction factor, the account that benefits from the deduction, and the covered instance.
The usage details page allows you to filter data by Start time, Account, Instance name, Covered instance ID, and Billing cycle of covered service. The details table also includes columns such as Remaining amount before deduction, Deducted amount, Remaining amount after deduction, Covered service, Covered billable item, Original instance usage, Start time, and End time.
View usage status
Check the utilization of a reserved instance to identify underuse and its coverage to verify cost reductions. Use this information to optimize your reserved instances.
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Utilization is the percentage of your reserved instance commitment used by matching instances. Higher utilization indicates better cost-effectiveness.
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Coverage shows the percentage of your total instance usage that reserved instances cover. Higher coverage indicates that your reserved instances are effectively reducing your costs.
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In the Actions column of the reserved instance list, click View Bills.
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On the Utilization Overview and Coverage Overview tabs, view the utilization and coverage of the current reserved instance.
Utilization
On the Reserved Instance Utilization Overview tab, the time granularity is set to Day and the time range is from 2024-10-22 to 2024-10-23. The top of the page displays four summary metrics: Total On-Demand Instance Cost, Total RI Purchase Cost, Total Savings, and Potential Total Savings. The utilization line chart shows that on 2024-10-22, the utilization was approximately 20% before it dropped to 0%. The table at the bottom lists details for each reserved instance, with columns such as Start/end time, Current status, Region, Zone, Type, Quantity, Operating system, Utilization, Deducted amount, Total RI amount, RI purchase cost, On-demand cost baseline, Net savings, and Potential net savings. For example, an expired
ecs.g6.largereserved instance with 21.66% utilization was underutilized.Coverage
On the Coverage Overview tab, the summary metrics show a Combined Coverage of 5.05%, Total Usage of 64.32 compute units*hours, and Total Deduction of 3.25 compute units*hours. You can filter data by Time Granularity (Day/Week/Month) and Time Range. The coverage line chart displays the trend for the selected period. The table at the bottom lists coverage details for each pay-as-you-go instance, with columns such as Account, Product name, Product detail, Pay-as-you-go instance ID, Statistical period, Region, Type, Coverage, Deducted amount, Total usage, and Bill amount. For example, an ECS pay-as-you-go instance of the
ecs.g6.largetype has a Coverage of 21.31%, a Deducted Amount of 3.25 compute units*hours, and a Total Usage of 15.25 compute units*hours. Coverage report data is available three days after the billing cycle ends (T+3).
Related documentation
You can call the DescribeReservedInstances API operation to query details of your reserved instances.