Question

A company runs a stable fleet of 200 EC2 instances across production and staging for a monolithic Java application. The workload has been running unchanged for over a year with predictable steady-state utilization. A FinOps review found average CPU utilization is 12% and memory utilization is 30%, and all instances are billed at On-Demand rates. The Solutions Architect must reduce compute cost with minimal application refactoring while preserving the ability to change instance families over time. Which combination of actions provides the greatest sustained cost reduction with the least operational risk?

Accepted Answer

Use AWS Compute Optimizer recommendations to rightsize instances to smaller types, then purchase Compute Savings Plans to cover the reduced steady-state usage.

Answer

Migrate all instances to Spot Instances managed by an Auto Scaling group with mixed instance policies to maximize discounts.

Answer

Purchase Standard Reserved Instances for the current instance types at the current fleet size to lock in the largest discount immediately.

Answer

Enable EC2 Auto Scaling with target tracking on CPU and rely on On-Demand pricing to scale down idle capacity.