AWS Certified Database – Specialty — Question 176

A gaming company has implemented a leaderboard in AWS using a Sorted Set data structure within Amazon ElastiCache for Redis. The ElastiCache cluster has been deployed with cluster mode disabled and has a replication group deployed with two additional replicas. The company is planning for a worldwide gaming event and is anticipating a higher write load than what the current cluster can handle.
Which method should a Database Specialist use to scale the ElastiCache cluster ahead of the upcoming event?

Answer options

• A. Enable cluster mode on the existing ElastiCache cluster and configure separate shards for the Sorted Set across all nodes in the cluster.
• B. Increase the size of the ElastiCache cluster nodes to a larger instance size.
• C. Create an additional ElastiCache cluster and load-balance traffic between the two clusters.
• D. Use the EXPIRE command and set a higher time to live (TTL) after each call to increment a given key.

Correct answer: B

Explanation

The correct answer is B because increasing the instance size of the ElastiCache cluster nodes directly addresses the anticipated higher write load by providing more resources. Option A would require a significant redesign of the cluster, which is not ideal for immediate scaling. Option C introduces complexity and does not directly increase the capacity of the existing cluster. Option D does not effectively scale the system; it merely manages key expiration without increasing throughput.