If you enable the lifecycle management feature of your General-purpose NAS file system, infrequently accessed data in the file system is transitioned to an Infrequent Access (IA) storage medium. When the specified lifecycle management policy is met, you are charged for the space usage of the IA storage medium and read/write traffic. This topic describes the billing items and billing methods of a General-purpose NAS file system whose lifecycle management feature is enabled. This topic also provides a billing example.

Billing items

Billing item Description
Usage fee of General-purpose NAS The maximum used storage space of the file system. Fees are calculated based on the maximum used storage space within each hour.
  • The used storage space is the total size of all files in a file system, excluding the size of directories. The minimum billing size of a file is 4 KB. If the size of a file is less than 4 KB, the billing size of the file is rounded up to 4 KB. For example, if the size of a file is 3 KB, the size of the file is counted as 4 KB.
  • The fees that are incurred within the last hour are calculated in the current hour. For example, if the current time is 9:30, the current hourly bill consists of the fees that are incurred from 8:00 to 9:00. If you use a NAS file system for less than one hour, you are still billed for the usage time of one hour. Due to latency, the bill that you can view at 9:30 is generated for the hour from 7:00 to 8:00.
  • You can log on to the NAS console and view the usage of storage space in the Basic Information section. The usage is updated every one hour. Due to latency, the usage displayed in the console may be different from the actual usage within the last hour.
  • File holes occupy storage space in NAS. Therefore, you are billed for the file holes in your NAS file system. A file hole consists of bytes that are not written to a file. These bytes are null characters. A file hole can be created by using the truncate, Iseek, or fallocate command.
usage of an IA storage
Read/write traffic Traffic fees are incurred when data in an IA storage medium is accessed. Fees are calculated based on the total amount of read/write traffic within each hour. The amount of read/write traffic is reset to 0 after an hourly bill is generated. Then, the calculation of read/write traffic amount is resumed in the next hour.

Billing methods

  • Pay-as-you-go
    Formula: Space usage fee = Usage fee of General-purpose NAS + Usage fee of IA storage medium + Traffic fee of IA storage medium= Maximum usage of a General-purpose NAS file system per hour × Unit price per hour + Maximum usage of an IA storage medium per hour × Unit price per hour + Amount of read traffic × Unit price per hour + Amount of write traffic × Unit price per hour
    Note
    • If the lifecycle management feature is enabled, the usage of General-purpose NAS in the preceding formula is the used storage space of the data that is not transitioned to an IA storage medium.
    • Read/write traffic of IA storage media supports only the pay-as-you-go billing method.
    • The unit of the space usage fee in the pricing of NAS is USD/GB/month. In the pay-as-you-go billing method, the fees are equal to the used storage space multiplied by the unit price per hour. You must convert the unit USD/GB/month to USD/GB/hour when you calculate the fee for the used storage space. For example, if the unit price of the Capacity NAS space usage in the China (Hangzhou) region is 0.06 USD/GB/month, the unit price of the space usage per hour is 0.000083 USD/GB/hour. The formula is: Unit price of space usage per hour = Unit price / (30 days × 24 hours). For more information, see Apsara File Storage NAS pricing.
  • Storage package
    You can purchase a storage package to deduct the service fees of General-purpose NAS. You can reduce costs by using storage packages. The following rules apply when you use a storage package:
    • A storage package is used to first deduct the fees for the used storage space. Then, if the storage package still has a positive balance, the storage package is used to deduct the fees for the used space of an IA storage medium based on a specified coefficient.
      • The storage package is sufficient to deduct all of the fees for the usage of the IA storage medium if the following condition is met: (Capacity of the storage package - Usage of the General-purpose NAS file system) × Coefficient - Usage of the IA storage medium ≥ 0 GB.
      • The storage package is insufficient to deduct all of the fees for the usage of the IA storage medium if the following condition is met: (Capacity of the storage package - Usage of the General-purpose NAS file system) × Coefficient - Usage of the IA storage medium < 0 GB. The fees for the remaining used storage space are calculated based on the pay-as-you-go billing method.

        The coefficient in the preceding formulas varies depending on the type of a file system. For Performance NAS file systems, the coefficient is 12.333. For Capacity NAS file systems, the coefficient is 2.333.

    • A storage package does not limit the storage capacity of a file system. The maximum storage capacity of a Capacity NAS instance is 1 PB. The maximum storage capacity of a Performance NAS instance is 10 PB.
      Note For example, you purchase a 100 GB storage package for the Performance NAS file system named A. During a billing cycle, the used storage space of file system A is 180 GB. The fee of 100 GB is deducted by the storage package, and the fee of the remaining 80 GB is calculated based on the pay-as-you-go billing method.
    • Storage packages and General-purpose NAS have the following relationships:
      • A General-purpose NAS file system can be attached to only one storage package at a time. When you delete a General-purpose NAS file system, the attached storage package is detached. You can attach the detached storage package to another General-purpose NAS file system. However, the file system must belong to the same type and reside in the same region as the file system that you delete.
      • A storage package is related to the storage type of a file system. For example, if you delete a Capacity NAS file system to which a storage package is attached, the detached storage package cannot be attached to a Performance NAS file system. If you delete a Performance NAS file system to which a storage package is attached, the detached storage package cannot be attached to a Capacity NAS file system.
      • A storage package is unrelated to the protocol type that is used by a file system. For example, if you delete a file system to which a storage package is attached and the file system uses the Network File System (NFS) protocol, the detached package can be attached to a file system that uses the Server Message Block (SMB) protocol.
    • When a storage package expires or the used space exceeds the capacity of the storage package, you are charged based on the pay-as-you-go billing method. You are charged for the data stored in your NAS file systems. No fee is incurred when the space usage is 0 GB. If you no longer need NAS, we recommend that you delete your file systems or delete all your data from NAS.
    • You can manually renew a storage package within the validity period of the storage package. You can also enable the auto-renewal feature. For more information, see Renew a storage package. You can upgrade a storage package based on your business requirements. For more information, see Upgrade a storage package.

Examples

In this example, Mr. Zhang has created a Capacity NAS file system named A in the China (Beijing) region. The used storage space of file system A from 10:00 to 11:00 on July 1, 2020 was 1,000 GB. A total of 200 GB data was stored in a General-purpose NAS file system, and 800 GB of data was stored in an IA storage medium. The amount of read traffic in the IA storage medium is 1 GB within this hour, and the amount of write traffic in the IA storage medium is 2 GB. The following tables list the fees that were incurred by file system A within the hour based on the pay-as-you-go and storage package billing methods.
Table 1. Pay-as-you-go
Billing item Fee
Usage of the General-purpose NAS file system Space usage fee = 200 GB × 0.06 USD/GB/month / 30 days / 24 hours = USD 0.0166666667
Usage of the IA storage medium Space usage fee = 800 GB × 0.0000322450 USD/GB/month / 30 days / 24 hours = USD 0.0000358277
Read/write traffic Read traffic Read traffic fee = 1 GB × 0.0092866000 USD/GB = USD 0.0092866000
Write traffic Write traffic fee = 2 GB × 0.0092866000 USD/GB = USD 0.0185732000
Hourly space usage fee = USD 0.0166666667 + USD 0.0000358277 + USD 0.0092866000 + USD 0.0185732000 = USD 0.0445622944
If Mr. Zhang used the same amount of storage space in file system A within each hour of the month, the monthly fee is calculated by using the following formula: Monthly fee = USD 0.0445622944 × 24 hours × 30 days = USD 32.084851968
Table 2. Storage package (500 GB, 1 month)
Billing item Fee
Usage of the General-purpose NAS file system Space usage fee = 200 GB × 23 USD/month / 30 days / 24 hours / 500 GB = USD 0.0127777778

where, USD 23 is the fee for the storage package (500 GB, 1 month).

Usage of the IA storage medium (500 GB -200 GB) × 2.333 - 800 GB = -100.01 GB < 0 GB. Therefore, the storage package is insufficient to deduct all of the fees for the usage of the IA storage medium.

The fees for the remaining used storage space are calculated based on the pay-as-you-go billing method. Space usage fee = 100.1 GB × 0.0000322450 USD/GB/month / 30 days / 24 hours = USD 0.0000044829

Read/write traffic Read traffic Read traffic fee = 1 GB × 0.0092866000 USD/GB = USD 0.0092866000
Write traffic Write traffic fee = 2 GB × 0.0092866000 USD/GB = USD 0.0185732000
Hourly space usage fee = USD 0.0127777778 + USD 0.0000044829 + USD 0.0092866000 + USD 0.0185732000 = USD 0.0406420607
If Mr. Zhang used the same amount of storage space in file system A within each hour of the month, the monthly fee is calculated by using the following formula: Monthly fee = USD 0.0406420607 × 24 hours × 30 days = USD 29.262283704