Question #1367
A company operates a DynamoDB table that handles a steady and predictable volume of read and write requests. The company aims to minimize costs while ensuring consistent performance. Which solution is MOST cost-effective?
Use DynamoDB Standard-Infrequent Access (Standard-IA) table class with provisioned throughput and reserve capacity for the workload.
Use provisioned throughput with read capacity units (RCUs) and write capacity units (WCUs) tailored to the forecasted workload.
Use on-demand mode with auto-scaling to dynamically adjust capacity based on real-time demand.
Use on-demand mode with DynamoDB Accelerator (DAX) to cache frequently accessed data.
Explanation
Answer B is correct because:
- Steady & Predictable Workload: Provisioned throughput allows precise capacity allocation matching the forecasted demand, avoiding over-provisioning costs.
- Cost Efficiency: Provisioned throughput is cheaper than on-demand (up to 80% less) for predictable traffic, as on-demand charges a premium for flexibility.
- Why Not Other Options:
- A: Standard-IA is for infrequently accessed data, not steady workloads. Reserved capacity isn't necessary if usage is predictable.
- C: On-demand auto-scaling incurs higher costs for predictable workloads.
- D: DAX adds caching costs, and on-demand is more expensive than provisioned.
Key Takeaway: Use provisioned throughput for predictable workloads to minimize costs while ensuring consistent performance.
Answer
The correct answer is: B