AWS Compute Optimizer

What it is

AWS Compute Optimizer analyzes the configuration and utilization metrics of your AWS resources and gives rightsizing recommendations and finds idle resources. It reports whether each resource is optimal (or over- or under-provisioned) and suggests changes that reduce cost and improve performance, with graphs of recent and projected utilization to compare options.

Choose Compute Optimizer when a question asks which instance type or size to use, how to right-size EC2, EBS, Lambda, or containers based on actual usage, or how to find idle resources to stop.

Concepts

• Supported resources include:
  • EC2 instances and EC2 Auto Scaling groups.
  • EBS volumes.
  • Lambda functions (memory).
  • ECS services on Fargate.
  • Aurora and RDS databases.
  • Commercial software licenses.
  • NAT gatewaysNAT gatewayA managed VPC component that lets instances in private subnets start connections to the internet or other networks, while blocking connections started from outside. It is billed per hour and per gigabyte processed.Glossary entryClose, DynamoDB, ElastiCache, MemoryDB, DocumentDB, WorkSpaces, and SageMaker.
• Opt in: you must opt in before it analyzes your resources. From the management account of an organization, you can opt in just that account or all member accounts, and then see recommendations across the organization.
• Data: by default it analyzes the last 14 days of CloudWatch metrics. Enhanced infrastructure metrics, a paid feature for EC2, Auto Scaling groups, and RDS, extends the lookback to 93 days to capture monthly patterns.
• Findings also appear in the consoles of the supported services, such as the EC2 console.

Compute Optimizer or another option?

If the requirement is	Choose
Right-size instances, volumes, or Lambda memory from usage	AWS Compute Optimizer
Find idle resources across services	Compute Optimizer or Trusted Advisor
Broad cost, security, and limit checks	AWS Trusted Advisor
Analyze and forecast spending	AWS Cost Explorer
Savings Plans and Reserved InstanceRI (Reserved Instance)A billing discount for committing to an instance type in a Region or Availability Zone for one or three years. It is not an instance: running instances that match are billed at the lower rate. AWS now recommends Savings Plans instead.Glossary entryClose purchase recommendations	Cost Explorer recommendations

Reverse mindmap: when the question points here

• Yes, when the question says
  • Right-size EC2 instances from utilization→ leads to Compute Optimizer
  • Over-provisioned instances→ leads to Compute Optimizer findings
  • Best memory setting for Lambda→ leads to Compute Optimizer
  • Right-size EBS volumes or Fargate tasks→ leads to Compute Optimizer
• Improve the recommendations
  • Include monthly patterns→ leads to Enhanced infrastructure metrics, 93 days
  • All accounts in the organization→ leads to Opt in from the management account
• No, when the question says
  • Forecast our monthly bill→ leads to Cost Explorer
  • Security and service limit checks→ leads to Trusted Advisor

Key takeaways

• Compute Optimizer gives rightsizing and idle-resource recommendations from CloudWatch utilization data.
• It covers EC2, Auto Scaling groups, EBS, Lambda, ECS on Fargate, RDS and Aurora, and more.
• You must opt in; the management account can opt in the whole organization.
• The default lookback is 14 days; paid enhanced infrastructure metrics extend it to 93 days.

Sources

• AWS Compute Optimizer User Guide: What is AWS Compute Optimizer?
• AWS Compute Optimizer User Guide: Getting started
• AWS Compute Optimizer User Guide: Resource requirements
• AWS Compute Optimizer User Guide: Metrics analyzed by AWS Compute Optimizer
• AWS Compute Optimizer User Guide: Enhanced infrastructure metrics
• AWS Compute Optimizer pricing