How does CFS charge?

Currently, CFS provides services using a post-payment method. The charges are based on the real space used by a file system. There are no minimum, traffic or request fees. For CFS pricing information, please see the CFS Billing page.

How is the real space used by a file system for billing calculated?

CFS's billing system periodically collects the real space used by a file system, and uses the peak value collected within one hour as the basis for billing. The real storage space of a file system is the sum of the real storage space of all regular files. CFS does not charge for other types of directory entries other than files such as folders, soft links and special files.

How is the storage space of a regular file calculated?

CFS fragments a file with 1 MB as a basic granularity. Fragment is a basic unit of CFS for space statistics. The storage space of a file is the sum of the storage space of all the fragments.

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

• Rule 1: If the size of the last fragment of the file is less than 1 MB, align to 4 KB according to the size of the fragment and calculate the storage space;
• Rule 2: In other cases, if the fragment has been written with data, the storage space is calculated according to the size of the fragment, which is 1 MB;
• Rule 3: The minimum storage space for a file is 4 KB.

Here are a few examples:

• Example 1: A file has a size of 5 KB, so whether the file has been written or not, its storage space is 8 KB according to Rule 1;
• Example 2: A file has a size of 1,025 KB. The [1,024 KB, 1,025 KB) fragment has a storage space of 4 KB. Then, if the segment [0, 1,024 KB) has been written, the storage space is 1 MB+4 KB=1,028 KB; if it has not been written, the storage space is 0 MB+4 KB=4 KB;
• Example 3: A file has a size of 1 MB, and is never written. Its storage space is 4 KB according to Rule 3.

Are file holes billed?

According to the calculation rules for storage space described above, file holes do not generate real storage space and no fees are charged.

Will the bill continue to accrue after arrears?

After arrears, the CFS system will stop service and data will be retained for 7 days. During the suspension period, the data of the file system is not accessible, but it still consumes resources, so charges will continue. During the suspension period, the service resumes if the user successfully renews it. Otherwise, after 7 days, the file system will be forcibly deleted, resources will be released, and the data of the user cannot be retrieved.

Users should pay attention to arrears notices, keep sufficient account balances, and avoid file system downtime, resulting in unnecessary economic loss and data loss.