AWS Certified Solutions Architect – Professional — Question 108

Your company is getting ready to do a major public announcement of a social media site on AWS. The website is running on EC2 instances deployed across multiple Availability Zones with a Multi-AZ RDS MySQL Extra Large DB Instance. The site performs a high number of small reads and writes per second and relies on an eventual consistency model. After comprehensive tests you discover that there is read contention on RDS MySQL.
Which are the best approaches to meet these requirements? (Choose two.)

Answer options

• A. Deploy ElastiCache in-memory cache running in each availability zone
• B. Implement sharding to distribute load to multiple RDS MySQL instances
• C. Increase the RDS MySQL Instance size and Implement provisioned IOPS
• D. Add an RDS MySQL read replica in each availability zone

Correct answer: A, D

Explanation

The correct answers, A and D, address read contention effectively by using caching and read replicas to reduce load on the primary database. Option B, while a valid approach, is not as straightforward and may introduce complexity without guaranteed results. Option C may alleviate some performance issues but does not specifically tackle read contention as effectively as the other options.