About This Domain
Domain 4 — Design Cost-Optimized Architectures — accounts for 20% of the SAA-C03 certification exam. This domain evaluates your understanding of ec2 pricing models: on-demand, reserved, savings plans, spot, s3 storage class selection and lifecycle policies, right-sizing compute resources, and related concepts. Domain 4 evaluates your ability to design cost-effective storage, compute, and database solutions, and apply cost optimization strategies. To pass this section you need practical knowledge of how these services and patterns work together in real-world architectures.
What You'll Be Tested On
- EC2 pricing models: On-Demand, Reserved, Savings Plans, Spot
- S3 storage class selection and lifecycle policies
- Right-sizing compute resources
- Serverless architectures for cost optimization
- Data transfer costs and optimization
- AWS Cost Explorer, Budgets, and Trusted Advisor
Key AWS Services in This Domain
Study Strategy for Domain 4
While 20% might seem like a smaller portion of the exam, every point counts toward the passing score. Focus on understanding core concepts and common exam scenarios for this domain. Don't neglect it — even a few missed questions here can make the difference between pass and fail.
Exam Tips for Domain 4
Compute Savings Plans offer the most flexibility compared to Reserved Instances.
S3 Intelligent-Tiering automates cost savings for data with unknown access patterns.
Spot Instances can save up to 90% but can be interrupted — use for fault-tolerant workloads.
Use S3 lifecycle policies to transition data to cheaper tiers automatically.
Frequently Asked Questions
How many questions on the SAA-C03 exam come from Domain 4?
Domain 4 (Design Cost-Optimized Architectures) makes up 20% of the SAA-C03 exam. The exam has 65 scored questions, so approximately 13 questions will come from this domain.
What services should I focus on for Domain 4?
The key services for this domain include EC2, S3, Lambda, DynamoDB, RDS, Organizations, Athena, Auto Scaling. Make sure you understand how each service works, its use cases, and how they integrate with one another.
How should I prepare for Design Cost-Optimized Architectures questions?
Start by reviewing the key topics listed above, then practice with domain-specific questions. Focus on understanding real-world scenarios rather than memorizing facts. Use our practice quizzes to test your knowledge and review explanations for any questions you get wrong.
What's the best order to study the SAA-C03 domains?
Many candidates start with the highest-weighted domains first. For the SAA-C03 exam, the domains in order of weight are: Design Secure Architectures (30%), Design Resilient Architectures (26%), Design High-Performing Architectures (24%), Design Cost-Optimized Architectures (20%). However, start with whichever domain aligns best with your existing experience.
Practice Domain 4 Questions
Test your knowledge of Design Cost-Optimized Architectures with practice questions from our SAA-C03 question bank.
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