Which solution will meet these requirements?
Use Spot Instances for the entire workload.
Use Reserved Instances for the baseline level of usage. Use Spot instances for any additional capacity that the application needs.
Use On-Demand Instances for the baseline level of usage. Use Spot Instances for any additional capacity that the application needs.
Use Dedicated Instances for the baseline level of usage. Use On-Demand Instances for any additional capacity that the application needs.
Explanations:
Spot Instances can be less reliable due to potential termination by AWS, especially during high-demand periods, which may lead to availability issues for the application.
Using Reserved Instances provides a cost-effective baseline for steady usage, while Spot Instances can efficiently handle additional demand during peak hours without sacrificing availability.
While On-Demand Instances ensure availability, they are more expensive than Reserved Instances, making this option less cost-effective for the baseline usage. Spot Instances may also not be reliable during peak usage times.
Dedicated Instances are more costly and are not necessary for this use case, where the focus is on minimizing costs. This option does not address the need for cost efficiency effectively.
I categorize that the answer is:
Use Reserved Instances for the baseline level of usage. Use Spot instances for any additional capacity that the application needs.