AWS Certified Database – Specialty — Question 121

A company is running a website on Amazon EC2 instances deployed in multiple Availability Zones (AZs). The site performs a high number of repetitive reads and writes each second on an Amazon RDS for MySQL Multi-AZ DB instance with General Purpose SSD (gp2) storage. After comprehensive testing and analysis, a database specialist discovers that there is high read latency and high CPU utilization on the DB instance.
Which approach should the database specialist take to resolve this issue without changing the application?

Answer options

• A. Implement sharding to distribute the load to multiple RDS for MySQL databases.
• B. Use the same RDS for MySQL instance class with Provisioned IOPS (PIOPS) storage.
• C. Add an RDS for MySQL read replica.
• D. Modify the RDS for MySQL database class to a bigger size and implement Provisioned IOPS (PIOPS).

Correct answer: D

Explanation

The correct answer is D because increasing the instance size and using Provisioned IOPS (PIOPS) storage can significantly enhance performance by providing more resources and faster I/O operations. Option A is incorrect as sharding would require application changes, while B might not provide sufficient improvements in performance. Option C, adding a read replica, could alleviate some read load but does not address the high CPU utilization on the primary instance.