AWS Certified Solutions Architect – Associate (SAA-C03)Design Cost-Optimized ArchitecturesMedium
A growing SaaS company uses Amazon RDS for MySQL as its primary database. The database is experiencing high CPU utilization during peak hours due to a large number of read queries from its analytics and reporting dashboards. The company wants to offload these read queries to reduce the load on the primary database and improve performance, while also ensuring a cost-optimized solution. Which action should the company take?
- AImplement Amazon ElastiCache for Redis to cache frequently accessed data.
- BMigrate the analytics and reporting dashboards to use a separate Amazon Redshift cluster.
- CUpgrade the primary RDS instance to a larger instance type with more CPU.
- DCreate an Amazon RDS Read Replica and configure the dashboards to query it.
Show answer & explanationAnswer & explanation
Correct answer: D. Create an Amazon RDS Read Replica and configure the dashboards to query it.
Creating an RDS Read Replica offloads read-heavy workloads from the primary instance, improving its performance and allowing the primary to focus on write operations. This is a cost-effective scaling solution for read-intensive applications without over-provisioning the primary database.
Why the other options are wrong
- A. ElastiCache can help reduce database load for highly repetitive, frequently accessed data, but it's a caching layer, not a direct solution for offloading diverse analytical read queries that still require database access.
- B. Migrating to Redshift is a valid solution for complex analytical queries, but for alleviating read load from an operational database, an RDS Read Replica is typically a more direct and cost-effective first step, especially if the reporting dashboards can tolerate slight replication lag.
- C. Upgrading the primary instance is a vertical scaling approach that can be more expensive and may not fully address the separation of read/write concerns, potentially leading to further bottlenecks later.
Amazon RDS Read Replicas
Amazon RDS Read Replicas provide an asynchronous copy of a primary database instance, allowing you to offload read traffic and improve database scalability.
- Improve read scalability by distributing read workloads.
- Can be promoted to a standalone database if needed.
- Cost-effective for read-heavy applications.
- Supports cross-Region and cross-AZ replication.
Memory trick: Read Replicas: Relieve Primary's Pressure, Preserve Pennies.