Inactive RDS Instance

Service Category

Database

Cloud Provider

AWS

Service Name

AWS RDS

Inefficiency Type

Unused Resource

Explanation

This inefficiency occurs when an RDS instance remains in the running state but is no longer actively serving application traffic. These instances may be remnants of retired applications, paused development environments, or workloads that were migrated elsewhere. If an instance shows no active connections and sustained inactivity across CPU and memory metrics, it is likely idle and generating unnecessary costs.

Relevant Billing Model

RDS instances are billed based on the selected instance class (vCPU and memory), per hour (or per second in some cases) while running. Additional charges may apply for storage, backup retention, Multi-AZ replication, and provisioned IOPS—regardless of workload activity.

Detection

Identify RDS instances that have been running continuously during the lookback period
Review performance metrics to confirm low or zero CPU and memory usage
Check connection logs and query metrics to validate the absence of active database traffic
Confirm with owners or application teams whether the instance is still in use
Evaluate whether snapshots or backups exist that could support future recovery needs

Remediation

Shut down or delete the inactive instance after validating that it is no longer required. Take a snapshot if data retention is necessary. Review and remove associated resources such as storage, backups, or read replicas to fully eliminate residual costs.

Relevant Documentation