Для Heavy Utilisation RI почасовая плата берётся даже в том случае, если инстанс выключен. Сравните (
http://aws.amazon.com/rds/reserved-instances/#2):
- Medium Utilization RIs –… Medium Utilization RIs allow you to turn off your DB Instance at any point and not pay the hourly fee.
- Heavy Utilization RIs –… You are charged this low hourly rate for every hour in the Reserved Instance term you purchase.
Для EC2 это более явно прописано (
http://aws.amazon.com/ec2/reserved-instances/#3):
Heavy Utilization Reserved Instances are billed for every hour during the entire Reserved Instance term (which means you’re charged the hourly fee regardless of whether any usage has occurred during an hour).
