Subscription is a billing method that allows you to use resources only after you pay for them. The subscription billing method for Hologres supports dynamic configuration changes. You can scale in or out Hologres resources based on your business needs. This topic describes the subscription billing method for Hologres.
Lifecycle management
 Instance expiration:
Assume that you purchase a Hologres instance based on the subscription billing method at the Alibaba Cloud International site (alibabacloud.com) and pay for computing and storage resources for four months in advance based on your business needs. You can use this instance immediately after successful payment. The Hologres instance is available to you for four months. After four months, Hologres stops providing services and the instance expires and enters the suspension state. To continue to use the instance, you must renew it based on the subscription billing method. If you do not renew your instance within 14 days during which no bill is pushed, the instance is released and deleted from the console. Data in the instance is also deleted and cannot be recovered.
 Overdue payment:
Assume that you purchase a Hologres instance based on the subscription billing method at the Alibaba Cloud International site (alibabacloud.com). However, your Alibaba Cloud account enters the overdue state during the use of the instance. Within 24 hours after the account is overdue, you can still use the instance. If you pay the arrears within this period, you can use the instance without interruption. If you do not pay the arrears within 24 hours, the instance is locked and cannot be accessed until it expires. The instance immediately enters the suspension state after it expires. You can continue to use the instance if you pay the arrears within 14 days after expiration. Otherwise, the instance is released and data in the instance is no longer retained.
Billable items and pricing
Billable item  Unit price 

Computing  The fee of computing resources varies based on different countries and regions.

Storage  The fee of storage resources varies based on different countries and regions.

Billing formula: Fee paid for subscription = Computing capacity × Unit price × Number of months that you want to use the instance + Storage space × Unit price × Number of months that you want to use the instance.
Billing example: Assume that you purchase an instance with 128 CUs of computing resources and 500 GB storage resources based on the subscription billing method in the Singapore region. If you want to use this instance for six months, the total fee is USD 25,099.344432, which is calculated based on the following formula: 128 CUs × USD 31.970149/CU/month × 6 months + 500 GB × USD 0.182090/GB/month × 6 months = USD 25,099.344432.
Configuration upgrade
If your Hologres instance that is purchased based on the subscription billing method does not have sufficient resources to meet your business needs, you can upgrade the instance configuration.
 Existing resources:
Amount paid for the existing resources = Computing capacity × Number of months you want to use the instance × Unit price + Storage space × Number of months you want to use the instance × Unit price
Amount used for the existing resources = Amount paid for the existing resources/Number of hours you want to use the instance × Number of hours you have used the instance
Amount remained for the existing resources = Amount paid for the existing resources  Amount used for the existing resources
 New resources:
Total amount to be paid for the new resources = Computing capacity × Number of months you want to use the instance × Unit price + Storage space × Number of months you want to use the instance × Unit price
Actual amount to be paid for the new resources = Total amount to be paid for the new resources/Number of hours you want to use the instance × Number of remaining hours you can use the instance
 Configuration upgrade:
Amount to be paid for upgrading the configuration of the instance = Actual amount to be paid for the new resources  Amount remained for the existing resources
 The amount paid for the existing resources is USD 4,092.179072, which is calculated based on the following formula: 64 CUs × 2 months × USD 31.970149/CU/month + 300 GB × 2 months × USD 0.182090/GB/month = USD 4,092.179072.
 The amount used for the existing resources is USD 818.4358144, which is calculated based on the following formula: USD 4,092.179072/1,440 hours × 288 hours = USD 818.4358144.
Note You have paid for existing resources for two months of 30 days. You have used the instance for 12 days from March 1 to March 13. The number of hours you want to use the instance is 1,440 hours, which is calculated based on the following formula: 2 months × 30 days/month × 24 hours/day = 1,440 hours. The number of hours you have used the instance is 288 hours, which is calculated based on the following formula: 12 days × 24 hours/day = 288 hours.
 The amount remained for the existing resources is USD 3,273.7432576, which is calculated based on the following formula: USD 4,092.179072  USD 818.4358144 = USD 3,273.7432576.
 The total amount to be paid for the new resources is USD 8,366.448144, which is calculated based on the following formula: 128 CUs × 2 months × USD 31.970149/CU/month + 500 GB × 2 months × USD 0.182090/GB/month = USD 8,366.448144.
 The actual amount to be paid for the new resources is USD 6,693.1585152, which is calculated based on the following formula: USD 8,366.448144/1,440 hours × 1,152 hours = USD 6,693.1585152.
Note You are expected to pay for the new resources for two months of 30 days. However, you can use the instance only for 48 days from March 13 to April 30. The number of hours you want to use the instance is 1,440 hours, which is calculated based on the following formula: 2 months × 30 days/month × 24 hours/day = 1,440 hours. The number of remaining hours you can use the instance is 1,152 hours, which is calculated based on the following formula: 48 days × 24 hours/day = 1,152 hours.
 The amount to be paid for upgrading the configuration of the instance is USD 145.672, which is calculated based on the following formula: USD 6,693.1585152  USD 3,273.7432576 = USD 145.672.
 In this example, each month is assumed to contain 30 days to simplify calculation.
 This example only illustrates the billing logic of configuration upgrade. Refer to your bill for the accurate amount.
Configuration downgrade
If resources allocated to your Hologres instance that is purchased based on the subscription billing method are excessive, you can downgrade the instance configuration to reduce costs.
 Existing resources:
Amount paid for the existing resources = Computing capacity × Number of months you want to use the instance × Unit price + Storage space × Number of months you want to use the instance × Unit price
Amount used for the existing resources = Amount paid for the existing resources/Number of hours you want to use the instance × Number of hours you have used the instance
Amount remained for the existing resources = Amount paid for the existing resources  Amount used for the existing resources
 New resources:
Total amount to be paid for the new resources = Computing capacity × Number of months you want to use the instance × Unit price + Storage space × Number of months you want to use the instance × Unit price
Actual amount to be paid for the new resources = Total amount to be paid for the new resources/Number of hours you want to use the instance × Number of remaining hours you can use the instance
 Configuration downgrade:
Amount to be paid for downgrading the configuration of the instance = Actual amount to be paid for the new resources  Amount remained for the existing resources
 The amount paid for the existing resources is USD 12,549.672216, which is calculated based on the following formula: 128 CUs × 3 months × USD 31.970149/CU/month + 500 GB × 3 months × USD 0.182090/GB/month = USD 12,549.672216.
 The amount used for the existing resources is USD 2,788.816, which is calculated based on the following formula: USD 12,549.672216/2,160 hours × 480 hours = USD 2,788.816.
Note You have paid for existing resources for three months of 30 days. You have used the instance for 20 days from March 1 to March 21. The number of hours you want to use the instance is 2,160 hours, which is calculated based on the following formula: 3 months × 30 days/month × 24 hours/day = 2,160 hours. The number of hours you have used the instance is 480 hours, which is calculated based on the following formula: 20 days × 24 hours/day = 480 hours.
 The amount remained for the existing resources is USD 9,760.856216, which is calculated based on the following formula: USD 12,549.672216  USD 2,788.816 = USD 9,760.856216.
 The total amount to be paid for the new resources is USD 6,302.149608, which is calculated based on the following formula: 64 CUs × 3 months × USD 31.970149/CU/month + 300 GB × 3 months × USD 0.182090/GB/month = USD 6,302.149608.
 The actual amount to be paid for the new resources is USD 4,901.67192, which is calculated based on the following formula: USD 6,302.149608/2,160 hours × 1,680 hours = USD 4,901.67192.
Note You are expected to pay for the new resources for three months of 30 days. However, you can use the instance only for 70 days from March 21 to May 31. The number of hours you want to use the instance is 2,160 hours, which is calculated based on the following formula: 3 months × 30 days/month × 24 hours/day = 2,160 hours. The number of remaining hours you can use the instance is 1,680 hours, which is calculated based on the following formula: 70 days × 24 hours/day = 1,680 hours.
 The amount to be paid for downgrading the configuration of the instance is USD 4,859.1843, which is calculated based on the following formula: USD 4,901.67192  USD 9,760.856216 = USD 4,859.1843.
 Alibaba Cloud needs to refund USD 4,859.1843 to your account.
 In this example, each month is assumed to contain 30 days to simplify calculation.
 This example only illustrates the billing logic of configuration downgrade. Refer to your bill for the accurate amount.
Message notification mechanism
The following table describes the message notification mechanism of Hologres instances in subscription mode.
Billing method  Reminder time for service suspension due to instance expiration  Downtime  Release reminder time 

Subscription  Seven days before expiration  The instance stops providing services immediately upon expiration.  Seven days before release 
Three days before expiration  Three days before release  
One day before expiration  One day before release 
Example: Assume that you purchase a Hologres instance based on the subscription billing method at the Alibaba Cloud International site (alibabacloud.com) and pay for computing and storage resources for two months in advance. You can receive expiration notifications by SMS, phone call, or email seven days, three days, and one day before the instance expires. The instance enters the suspension state when it expires. Then, Hologres stops providing services. If you do not renew your instance within 14 days, the system automatically releases the instance and sends release notifications by SMS, phone call, or email seven days, three days, and one day before the release.