This topic describes the billing items and billing methods of a General-purpose NAS file system. This topic also provides several billing examples.

Billing items

Billing item Description
Usage The maximum used storage space of a 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 KiB. If the size of a file is less than 4 KiB, the billing size of the file is rounded up to 4 KiB. For example, if the size of a file is 3 KiB, the size of the file is counted as 4 KiB.
  • The fees of 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 may be generated for the hour from 7:00 to 8:00.
  • You can log on to the Apsara File Storage 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, lseek, or fallocate command.

Billing methods

  • Pay-as-you-go
    Formula: Space usage fee = Maximum usage of a NAS file system per hour × Unit price per hour
    Note
    • General-purpose NAS includes two types of file systems: Capacity NAS and Performance NAS. The unit prices for each file system are different.
    • In the NAS pricing system, the unit of space usage fees is USD/GiB/month. If the pay-as-you-go billing method is adopted, fees are calculated based on the used storage space multiplied by the unit price per hour. You must convert USD/GiB/month into USD/GiB/hour when you calculate the fee for the used storage space. For example, if the unit price of the space usage of a Capacity NAS file system in the China (Hangzhou) region is 0.06 USD/GiB/month, the unit price of the space usage per hour is 0.000083 USD/GiB/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 resource usage fees of a General-purpose NAS file system. You can reserve resources and reduce costs by using storage packages. The following rules are applied when you use a storage package:
    • A storage package does not limit the storage capacity of a file system. The maximum storage capacity of a Capacity NAS file system is 1 PiB. The maximum storage capacity of a Performance NAS file system is 10 PiB.
      Note For example, you purchase a 100 GiB storage package for a Performance NAS file system named A. During a billing cycle, the used storage space of file system A is 180 GiB. The fee of 100 GiB is deducted by the storage package, and the fee of the remaining 80 GiB 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 storage package to another General-purpose NAS file system. However, the new file system must be of the same type and reside in the same region as the file system that you delete.
      • You can attach a storage package only to a file system whose storage type is the same as the storage package. 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.
      • You can attach a storage package to an arbitrary file system. You do not need to be concerned about the protocol type that is used. The detached package can be attached to a file system that uses the Server Message Block (SMB) protocol. For example, this applies if you delete a file system to which a storage package is attached and the file system uses the Network File System (NFS) protocol.
    • When a storage package expires or the used space exceeds the capacity of the storage package, you are billed based on the pay-as-you-go billing method. You are billed for the data stored in your NAS file systems. No fee is incurred when the space usage is 0 GiB. If you no longer use NAS, we recommend that you delete your file systems or delete all your data from these file systems.
    • 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

Example 1: Mr. Wang has created a Capacity NAS file system in the China (Hangzhou) region. The average space usage per hour in October of 2020 is 1,000 GiB. The following table lists the monthly fees that were incurred by the file system based on the pay-as-you-go and storage package billing methods.
Billing methods Fee
Pay-as-you-go Space usage fee = 1,024 GiB × 0.06 USD/GiB/month = USD 61.44
Storage package (500 GiB, 1 month) Space usage fee = USD 23 + (1024 GiB - 500 GiB) × 0.06 USD/GiB/month = USD 54.44

In the preceding equation, USD 23 is the fee for the storage package (500 GiB, 1 month).
Storage package (1 TiB, 1 month) Space usage fee = USD 48

In the preceding equation, USD 48 is the fee for the storage package (1 TiB, 1 month).
Example 2: Mr. Zhang has created a Performance NAS file system in the China (Hangzhou) region. The average space usage per hour in October of 2020 is 1,000 GiB. The following table lists the monthly fees that were incurred by the file system based on the pay-as-you-go and storage package billing methods.
Billing methods Fee
Pay-as-you-go Space usage fee = 1,024 GiB × 0.3 USD/GiB/month = USD 307.2
Storage package (500 GiB, 1 month) The fee of 500 GiB is deducted by the storage package, and the fee of the remaining space usage is calculated based on the pay-as-you-go billing method.

Space usage fee = USD 133 + (1024 GiB - 500 GiB) × 0.3 USD/GiB/month = USD 290.2

In the preceding equation, USD 133 is the fee for the storage package (500 GiB, 1 month).

Storage package (1 TiB, 1 month) Space usage fee = USD 272

In the preceding equation, USD 272 is the fee for the storage package (1 TiB, 1 month).