AWS Certified DevOps Engineer – Professional — Question 159

A company is using an Amazon API Gateway API and an AWS Lambda function to host a microservice. The microservice accesses pricing data in an Amazon DynamoDB table for the company’s online store.

Interest in the online store has increased. As a result, latency issues and throttling on the DynamoDB table are occurring when a specific query runs. Some internal services access the DynamoDB table directly. No caching is enabled for the current solution.

A DevOps engineer notices that repeat requests to the API are taking the same amount of time as unique requests. The DevOps engineer must reduce the latency for the repeat requests to the API and must reduce the throttling on the DynamoDB table.

Which solution will meet these requirements?

Answer options

• A. Enable caching for API Gateway stages. Use DynamoDB Accelerator (DAX) for the DynamoDB table.
• B. Enable caching tor API Gateway stages. Use Amazon ElastiCache for Memcached caching for the DynamoDB table.
• C. Use provisioned concurrency for the Lambda function. Use DynamoDB Accelerator (DAX) for the DynamoDB table.
• D. Use provisioned concurrency for the Lambda function. Increase the RCUs for the DynamoDB table.

Correct answer: A

Explanation

Option A is correct because enabling caching at the API Gateway can significantly reduce latency for repeat requests, while using DynamoDB Accelerator (DAX) helps to improve read performance and reduce throttling on the DynamoDB table. The other options either suggest solutions that do not address the caching needs effectively or fail to optimize the read performance of DynamoDB.