AWS Certified Solutions Architect – Associate (SAA-C03) — Question 632

A company performs tests on an application that uses an Amazon DynamoDB table. The tests run for 4 hours once a week. The company knows how many read and write operations the application performs to the table each second during the tests. The company does not currently use DynamoDB for any other use case. A solutions architect needs to optimize the costs for the table.

Which solution will meet these requirements?

Answer options

• A. Choose on-demand mode. Update the read and write capacity units appropriately.
• B. Choose provisioned mode. Update the read and write capacity units appropriately.
• C. Purchase DynamoDB reserved capacity for a 1-year term.
• D. Purchase DynamoDB reserved capacity for a 3-year term.

Correct answer: B

Explanation

Provisioned capacity mode is the most cost-effective choice because the workload's throughput is highly predictable and known in advance, allowing the company to adjust RCUs and WCUs specifically for the 4-hour window and scale them down when not in use. On-demand mode does not use manually configured capacity units and is typically more expensive for predictable traffic. Reserved capacity options are designed for continuous, 24/7 workloads and would result in wasted spend for a weekly 4-hour test.