Viewing idle resource recommendations
Compute Optimizer helps you identify idle resources that can be deleted or stopped to reduce your AWS cloud costs. Idle recommendations can be accessed through the Compute Optimizer console and our set of APIs. Idle recommendations are available for the following supported AWS resources:
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Amazon EC2 instances
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Auto Scaling groups
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Amazon EBS volumes
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Amazon ECS services on Fargate
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Amazon RDS databases
The recommendations are refreshed daily. These recommendations are generated by analyzing the specifications and utilization metrics of your AWS resources over the lookback period. The lookback period depends on the supported resource and your recommendation preference settings. If you don't have any recommednation preferences set, we use the default lookback period of 14 days. For more information, see Idle criteria per resource.
Note
For EBS volumes we analyze the attachment status over a 32-day lookback period.
Idle criteria per resource
Each of the supported resources eligible for idle recommendations has its own criteria to be found idle. The following table breaks down the idle criteria for each resource and also provides Compute Optimizer’s recommended action for the idle resource.
| Resource | Metric analyzed | Idle criteria | Recommended action |
|---|---|---|---|
|
Amazon EC2 instances |
CPU utilization and network IO |
The peak CPU utilization is below 5% and your network I/O is less than 5MB/day over the 14-day lookback period. |
Verify whether you need this instance. If you don't need it, consider deleting this instance. |
|
Auto Scaling groups |
CPU utilization and network IO |
The EC2 Auto Scaling group has no instances with more than 5% CPU utilization or 5MB/day network utilization over the 14-day lookback period. |
Verify whether you need this group. Consider scaling down this group to one instance or consider deleting it. |
|
Amazon EBS volumes |
Read/Write operations and attachment status |
Compute Optimizer can find an EBS volume to be idle or unattached.
|
Verify whether you need this volume. If you don't need it, we recommend that you create a snapshot of the volume and consider deleting it. |
|
Amazon ECS services on Fargate |
CPU utilization and memory utilization |
The peak CPU and memory utilization is below 1% over the 14-day lookback period. |
Verify whether your containerized application is running as expected. If the application is not running, consider deleting this service. |
|
Amazon RDS databases |
Database connections, read/write IOPS, and CPU utilization |
RDS for MySQL and RDS for PostgreSQL The DB instance is not a read replica, and had no database connections, low CPU usage, and low read/write activity over the lookback period. Aurora MySQL and Aurora PostgreSQL The DB instance is not part of a secondary cluster in an Aurora Global Database, and had no database connections, low CPU usage, and low read/write activity over the lookback period. |
Verify whether you need this DB instance. If you don’t need this instance temporarily, you can stop RDS MySQL and RDS PostgreSQL DB instances for up to 7 days. If you no longer need this instance, you can create a DB snapshot and delete the instance. For idle Aurora MySQL and Aurora PostgreSQL instances, you can also change the DB instance class to db.serverless. |
Estimated monthly savings
Estimated monthly savings (after discounts)
This column lists the approximate monthly cost savings that you experience by taking Compute Optimizer’s recommended action per idle resource under the supported pricing models. The supported pricing models depends on the specific AWS resource. For example, EC2 instances supports Savings Plans and Reserved Instances discounts but ECS services only supports the Savings Plans pricing model. To receive recommendations with supported pricing models, the savings estimation mode preference needs to be activated. For more information, see Savings estimation mode.
Note
If you don't activate the savings estimation mode preference, this column on both the Instance and Storage tabs display the default On-Demand pricing discount information.
Estimated monthly savings (On-Demand)
This column lists the approximate monthly cost savings that you experience by taking Compute Optimizer’s recommended action per idle resource under the On-Demand pricing model.
Important
If you enable Cost Optimization Hub in AWS Cost Explorer, Compute Optimizer uses Cost Optimization Hub data, which includes your specific pricing discounts, to generate your recommendations. If Cost Optimization Hub isn't enabled, Compute Optimizer uses Cost Explorer data and On-Demand pricing information to generate your recommendations. For more information, see Enabling Cost Explorer and Cost Optimization Hub in the in the AWS Cost Management User Guide.
