Which solution will meet this requirement MOST cost-effectively?
Use On-Demand Instances for the Amazon RDS for PostgreSQL workloads. Purchase a 1 year Compute Savings Plan with the No Upfront option for the EC2 instances.
Purchase Reserved Instances for a 1 year term with the No Upfront option for the Amazon RDS for PostgreSQL workloads. Purchase a 1 year EC2 Instance Savings Plan with the No Upfront option for the EC2 instances.
Purchase Reserved Instances for a 1 year term with the Partial Upfront option for the Amazon RDS for PostgreSQL workloads. Purchase a 1 year EC2 Instance Savings Plan with the Partial Upfront option for the EC2 instances.
Purchase Reserved Instances for a 3 year term with the All Upfront option for the Amazon RDS for PostgreSQL workloads. Purchase a 3 year EC2 Instance Savings Plan with the All Upfront option for the EC2 instances.
Explanations:
On-Demand Instances for Amazon RDS do not provide cost savings for long-term workloads. Although a 1-year Compute Savings Plan reduces EC2 costs, combining On-Demand RDS instances with EC2 Savings Plans isn’t cost-effective.
1-year No Upfront Reserved Instances and EC2 Instance Savings Plan offer some savings but are less cost-effective for long-term workloads compared to a 3-year plan or an All Upfront payment option.
1-year Partial Upfront Reserved Instances for RDS and Partial Upfront EC2 Savings Plans offer cost savings but remain less optimal for long-term workloads than a 3-year All Upfront plan.
3-year All Upfront Reserved Instances for Amazon RDS and EC2 provide the highest long-term savings, making it the most cost-effective choice for long-running workloads.
I guess:
Purchase Reserved Instances for a 3 year term with the All Upfront option for the Amazon RDS for PostgreSQL workloads. Purchase a 3 year EC2 Instance Savings Plan with the All Upfront option for the EC2 instances.