How should a database specialist configure the DynamoDB table’s capacity to meet these requirements MOST cost-effectively?
Use DynamoDB provisioned capacity with 5 WCUs and auto scaling.
Use DynamoDB provisioned capacity with 5 WCUs and a write-through cache that DynamoDB Accelerator (DAX) provides.
Use DynamoDB provisioned capacity with 10 WCUs and auto scaling.
Use DynamoDB provisioned capacity with 10 WCUs and no auto scaling.
Explanations:
While auto scaling would adjust to the 20 write requests per second during the automated job, it is not needed to meet the peak demand of 20 WCUs.
DAX is a read-through cache, not applicable for write throughput. Also, provisioned capacity with 5 WCUs does not meet the peak demand of 20 WCUs.
10 WCUs meets both the normal business day requirements (5 WCUs) and the peak requirements (20 WCUs for 1 hour) without needing auto scaling.
10 WCUs are required to meet peak demand, but no auto scaling is unnecessary. With auto scaling, costs could be reduced during off-peak hours.
As far as I’m aware, the answer is:
Use DynamoDB provisioned capacity with 10 WCUs and auto scaling.
I estimate that the answer is:
Use DynamoDB provisioned capacity with 10 WCUs and auto scaling.