Examkin

Question

Difficulty: MediumOptimizing Compute and Storage Performance

A company runs a three-tier web application on Amazon EC2 instances in an Auto Scaling group behind an Application Load Balancer (ALB). The application's database is a single-node Amazon RDS for PostgreSQL instance. During high-traffic events, users experience slow response times. System metrics indicate that EC2 CPU utilization remains below 35%35\%, but the RDS instance CPU utilization reaches 98%98\% due to a large volume of read-only reporting queries. Which architectural optimization should a solutions architect implement to resolve the performance bottleneck with the least operational overhead?

  1. Deploy Amazon RDS Read Replicas and configure the application to route read-only queries to the read replica endpoints.Answer
  2. B
    Enable Amazon RDS Multi-AZ replication to distribute the read-only reporting queries between the primary and standby database instances.
  3. C
    Request that AWS Support pre-warm the Application Load Balancer to ensure it scales ahead of high-traffic events and reduces latency.
  4. D
    Deploy an Amazon ElastiCache for Memcached cluster with Multi-AZ replication to cache the query results and persistent database sessions.

Answer

Deploy Amazon RDS Read Replicas and configure the application to route read-only queries to the read replica endpoints.
Deploying Amazon RDS Read Replicas is the correct strategy because it allows the read-only reporting queries to be directed to a separate read replica endpoint. This offloads read traffic from the primary database instance, lowering its CPU utilization and resolving the performance bottleneck without requiring significant application refactoring.

Step-by-Step Solution

1
Identify the primary source of the performance bottleneck.
EC2 instances have low CPU utilization (<35%<35\%), but the RDS database has extremely high CPU utilization (98%98\%) due to read-only queries.
Resolving the database CPU bottleneck is the key to improving application response times.
2
Select the correct optimization strategy for read-heavy RDS databases.
RDS Read Replicas are identified as the standard mechanism to offload read-only traffic from the primary instance.
Routing reporting queries to read replicas directly reduces the primary database CPU workload without modifying the database engine.

Key Concept

Horizontal scaling of database workloads using Read Replicas versus High Availability configurations.
Rate this question

Topics

Optimizing Compute and Storage Performance