Cost Optimization Improvement Strategy — AWS Solutions Architect (SAA-C03)
Each cost profile maps to a specific optimization lever
"Unpredictable workload with occasional peaks" signals Spot or Lambda. "Consistent baseline with steady growth" signals Reserved Instances or Savings Plans. "Idle resources nights and weekends" signals scheduled Auto Scaling or an instance scheduler. "High data transfer costs between services" signals a VPC endpoint evaluation. Candidates apply Reserved Instances as a general-purpose cost answer. The exam uses workload description as a filter: each cost profile maps to a specific mechanism, and applying the wrong lever to the wrong profile is itself a distractor.
What This Pattern Tests
The exam presents a running environment and tests ongoing cost optimization. AWS Cost Explorer shows spend trends and forecasts. Trusted Advisor flags idle resources (unattached EBS volumes at $0.10/GB/month, idle RDS instances, underutilized EC2). Cost Anomaly Detection alerts on unexpected spend spikes. Compute Optimizer recommends instance rightsizing. The trap is treating cost optimization as a one-time exercise — the exam tests whether your answer includes continuous monitoring, not just a one-time review. Savings Plans and Reserved Instances are the last step, after eliminating waste and rightsizing.
Decision Axis
Optimization sequence: eliminate waste first, rightsize second, optimize pricing third. Continuous monitoring, not one-time review.
Associated Traps
More Top Traps on This Exam
Decision Rules
Which S3 storage class satisfies a millisecond retrieval SLA at minimum cost for objects that become infrequently accessed after approximately 60 days?
Whether cold historical records accessed less than once per quarter should remain in RDS at gp3 per-GB-month pricing—or be exported and archived to an S3 storage class tuned for infrequent access—given that long-lived in-database cold data volume, not engine or instance tier, is the dominant cost driver.
Domain Coverage
Difficulty Breakdown