This topic describes the fees for configuration changes to pay-as-you-go and subscription clusters.

Pay-as-you-go

Pay-as-you-go clusters are charged on an hourly basis. After you change the configurations of a pay-as-you-go cluster, the cluster is charged at the new price on an hourly basis.

Subscription

Change type Description
Upgrade specifications or add nodes Payment = Total fees of the new configurations for the remaining subscription period (Monthly price of the new configurations/30/24 × Remaining subscription period measured in hours) - Total fees of the original configurations for the remaining subscription period (Monthly price of the original configurations/30/24 × Remaining subscription period measured in hours)

For example, the monthly price of the new configurations is USD 14,400. The monthly price of the original configurations is USD 7,200. The remaining subscription period is 50 days. The payment is calculated based on the following formula: (USD 14,400/30/24 × 50 × 24) - (USD 7,200/30/24 × 50 × 24) = USD 12,000.

Downgrade specifications or delete nodes

Refund = Total fees of the original configurations for the remaining subscription period (Monthly price of the original configurations/30/24 × Remaining subscription period measured in hours) - Total fees of the new configurations for the remaining subscription period (Monthly price of the new configurations/30/24 × Remaining subscription period measured in hours).

For example, to purchase a subscription cluster for three months, you are charged USD 3,500. You pay USD 3,000 for the cluster after you use coupons. After two months, the total fees of the original configurations for the remaining subscription period become USD 1,000. The total fees of the new configurations for a month are USD 800. The refund is calculated based on the following formula: USD 1,000 - USD 800 = USD 200.

Note You can receive a refund for a downgraded configuration of a subscription cluster. However, fees for the entire cluster cannot be refunded. If you want to apply for a refund for the entire cluster, submit a ticket. If your application is approved, your subscription cluster is frozen and will be deleted after 14 days.

FAQ

Why is my received refund less than the refund that I calculated for the downgraded configurations of the cluster?

Check the following scenarios before you downgrade the cluster configurations:

  • You are offered discounts for the order of the original configurations. For example, if you purchase the cluster on the International site (alibabacloud.com) and the subscription period is one year or longer, you are offered a 15% discount. Assume that the original price of the cluster is USD 1,000 and you pay USD 850 for the cluster. If you downgrade the cluster configurations, USD 850 is used as the payment amount to calculate the refund of the downgrade.
  • Assume that you use coupons for the order of the original configurations and you pay USD 500 for the order. If you downgrade the cluster configurations, USD 500 is used as the payment amount to calculate the refund of the downgrade.

References

  • Manual configuration change

    You can manually upgrade or downgrade the configurations of a cluster. For more information, see Manually upgrade or downgrade a PolarDB cluster and Add or remove read-only nodes.

  • Automatic configuration change

    You can use PolarDB for MySQL and the automatic scale-out and automatic scale-in features of Database Autonomy Service (DAS) to automatically change cluster configurations. For more information about the automatic scale-out and automatic scale-in features, see Autonomy center. You can customize the conditions that trigger automatic scale-out and scale-in activities based on the fluctuations of your workloads. When the trigger conditions are met, PolarDB for MySQL automatically upgrades or downgrades the cluster configurations by level.