Billing Problems

How is CFS charged

Currently, CFS offers two charge types: pay-as-you-go and storage package billing. Charges are based solely on the actual storage space used by a file system, with no minimum fee, traffic fee, or request fee. For detailed CFS pricing information, please visit the [CFS Billing](CFS/Product pricing/Pay as you go.md) page.

How is the actual storage space used for billing of a file system calculated

The CFS billing system periodically collects data on the actual storage space used by a file system, and uses the peak value collected within an hour as the basis for billing. The actual storage space of a file system is the sum of the actual storage space of all regular files. CFS does not charge for directory entries other than files, such as folders, symlinks, and special files.

How is the storage space of a regular file calculated

CFS breaks a file into fragments of 1 MB as the basic granularity. These fragments serve as the foundational unit for CFS storage space statistics. The storage for a file is calculated as the sum of the space occupied by all its fragments.

The storage space of each fragment is calculated according to the following rules:

• Rule 1: If the size of the last fragment of a file is less than 1 MB, its storage space is calculated by aligning the fragment size to 4 KB;
• Rule 2: In other cases, if data has been written to a fragment, its storage space is calculated as the full size of the fragment (i.e., 1 MB);
• Rule 3: The minimum storage space for a single file is 4 KB.

Here are some examples for illustration:

• Example I: If a file is 5 KB in size, its storage space is 8 KB according to Rule 1, regardless of whether data has been written to it;
• Example II: If a file is 1,025 KB in size, the storage space of the fragment [1,024 KB, 1,025 KB) is 4 KB. If data has been written to the fragment [0, 1,024 KB), the total storage space is 1 MB + 4 KB = 1,028 KB. If no data has been written to this fragment, the total storage space is 0 MB + 4 KB = 4 KB.
• Example III: For a 1 MB file where no data has ever been written, its storage space, according to Rule 3, will be 4 KB.

Is file sparsity charged

According to the storage space calculation rules outlined above, file sparsity does not consume actual storage space and therefore incurs no charges.

Will charges continue to accrue after arrears

If arrears occur, the CFS system will suspend the service, though the data will be retained for 15 days. During this suspension, the file system data will remain inaccessible but will continue to occupy resources, leading to ongoing charges. If the service is renewed successfully during this period, it will be restored. Otherwise, after 15 days, the system will forcibly delete the file system, release the resources, and permanently erase the data.

Users should pay attention to arrears notifications, ensure sufficient account balances, and avoid file system service suspension to prevent unnecessary financial losses and irretrievable data loss.

Can purchasing a storage package increase the maximum throughput of a file system

No. The maximum throughput of a CFS file system increases linearly with the actual usage. Storage packages can only offset usage fees and have no connection to the maximum throughput. For more information, please refer to the Product Specifications page.