Rightsizing is the cloud concept that is demonstrated by using AWS Compute Optimizer. Rightsizing is the process of adjusting the type and size of your cloud resources to match the optimal performance and cost for your workloads. AWS Compute Optimizer is a service that analyzes the configuration and utilization metrics of your AWS resources, such as Amazon EC2 instances, Amazon EBS volumes, AWS Lambda functions, and Amazon ECS services on AWS Fargate. It reports whether your resources are optimal, and generates optimization recommendations to reduce the cost and improve the performance of your workloads. AWS Compute Optimizer uses machine learning to analyze your historical utilization data and compare it with the most cost-effective AWS alternatives. You can use the recommendations toevaluate the trade-offs between cost and performance, and decide when to move or resize your resources to achieve the best results. References: Workload Rightsizing - AWS Compute Optimizer - AWS, What is AWS Compute Optimizer? - AWS Compute Optimizer