Q9 — AWS SAA-C03 Ch.14

Question 9 of 100 | ← Chapter 14

Q1009. A company uses an Amazon RDS for MySQL instance. To prepare for end-of-year processing, the company added a read replica to accommodate extra read-only queries from the company's reporting tool. The read replica CPU usage was 60% and the primary instance CPU usage was 60%.After end-of-year activities are complete, the read replica has a constant 25% CPU usage. The primary instance still has a constant 60% CPU usage. The company wants to rightsize the database and still provide enough performance for future growth.Which solution will meet these requirements?

• A. Delete the read replica Do not make changes to the primary instance
• B. Resize the read replica to a smaller instance size Do not make changes to the primary instance ✓
• C. Resize the read replica to a larger instance size Resize the primary instance to a smaller instance size
• D. Delete the read replica Resize the primary instance to a larger instance

Correct Answer: B. Resize the read replica to a smaller instance size Do not make changes to the primary instance

Explanation

To rightsize the database while ensuring enough performance for future growth, the best solution is:B. Resize the read replica to a smaller instance size. Do not make changes to the primary instance.Explanation:\1. Current Usage: - The read replica has a constant CPU usage of 25%, indicating that it is underutilized. Resizing it to a smaller instance will reduce costs without impacting performance since it will still be able to handle the read workload.\2. Primary Instance Usage: - The primary instance's CPU usage remains at 60%, which indicates it is actively processing queries and is likely sized appropriately for the current workload. Keeping it at its current size is a prudent decision, especially if future growth is anticipated.\3. Future Growth Consideration: - By resizing the read replica downwards, the company can save costs while ensuring that the primary instance remains capable of supporting the workload. This approach also maintains the availability of the read replica for read queries, which is crucial for performance during peak times.Evaluation of Other Options:A. Delete the read replica. Do not make changes to the primary instance: This would eliminate the additional read capacity, which could negatively impact performance during peak read times, especially if future growth occurs.C. Resize the read replica to a larger instance size. Resize the primary instance to a smaller instance size: This is unnecessary since the read replica is underutilized. Increasing its size would incur additional costs without a performance benefit. Additionally, reducing the primary instance size may lead to performance issues given its current 60% CPU usage.D. Delete the read replica. Resize the primary instance to a larger instance: This is not advisable since the primary instance is already operating at a high CPU usage level. There’s no justification for increasing its size without clear evidence that it is required for performance.Conclusion:Option B is the most cost-effective solution that maintains performance while accommodating future growth, as it effectively utilizes resources without incurring unnecessary costs.