AWS Certified Solutions Architect – Associate (SAA-C02) — Question 351

An online shopping application accesses an Amazon RDS Multi-AZ DB instance. Database performance is slowing down the application. After upgrading to the next-generation instance type, there was no significant performance improvement.
Analysis shows approximately 700 IOPS are sustained, common queries run for long durations and memory utilization is high.
Which application change should a solutions architect recommend to resolve these issues?

Answer options

• A. Migrate the RDS instance to an Amazon Redshift cluster and enable weekly garbage collection.
• B. Separate the long-running queries into a new Multi-AZ RDS database and modify the application to query whichever database is needed.
• C. Deploy a two-node Amazon ElastiCache cluster and modify the application to query the cluster first and query the database only if needed.
• D. Create an Amazon Simple Queue Service (Amazon SQS) FIFO queue for common queries and query it first and query the database only if needed.

Correct answer: C

Explanation

Deploying an Amazon ElastiCache cluster allows the application to cache the results of frequent, resource-intensive queries, which significantly reduces the read load, memory consumption, and IOPS on the Amazon RDS DB instance. Amazon Redshift is designed for analytical warehousing rather than transactional e-commerce workloads, making Option A incorrect. Amazon SQS is a message queuing service, not a caching solution, and splitting the database into multiple RDS instances adds unnecessary complexity without addressing the root cause of repeated query execution.