AWS Certified Solutions Architect – Professional (SAP-C02) — Question 480

A company is running a serverless ecommerce application on AWS. The application uses Amazon API Gateway to invoke AWS Lambda Java functions. The Lambda functions connect to an Amazon RDS for MySQL database to store data.

During a recent sale event, a sudden increase in web traffic resulted in poor API performance and database connection failures. The company needs to implement a solution to minimize the latency for the Lambda functions and to support bursts in traffic.

Which solution will meet these requirements with the LEAST amount of change to the application?

Answer options

• A. Update the code of the Lambda functions so that the Lambda functions open the database connection outside of the function handler. Increase the provisioned concurrency for the Lambda functions.
• B. Create an RDS Proxy endpoint for the database. Store database secrets in AWS Secrets Manager. Set up the required IAM permissions. Update the Lambda functions to connect to the RDS Proxy endpoint. Increase the provisioned concurrency for the Lambda functions.
• C. Create a custom parameter group. Increase the value of the max_connections parameter. Associate the custom parameter group with the RDS DB instance and schedule a reboot. Increase the reserved concurrency for the Lambda functions.
• D. Create an RDS Proxy endpoint for the database. Store database secrets in AWS Secrets Manager. Set up the required IAM permissions. Update the Lambda functions to connect to the RDS Proxy endpoint. Increase the reserved concurrency for the Lambda functions.

Correct answer: B

Explanation

Amazon RDS Proxy resolves database connection scaling issues by pooling and sharing database connections, which prevents the connection failures associated with rapid Lambda scaling. Using provisioned concurrency pre-warms the Java-based Lambda functions, effectively minimizing the cold-start latency during sudden traffic bursts. Other options using reserved concurrency are incorrect because reserved concurrency limits maximum scaling and does not address cold-start latency.