ApsaraDB RDS:Backup storage fees

Billable items

Billing rules

A free quota on storage is provided for each RDS instance to store backup files. If the total size of the backup files of your RDS instance does not exceed the free quota, no fees are charged. For more information, see View and manage the size of backup files. If the total size exceeds the free quota, you are charged an hourly fee for the excess backup storage that you use. The hourly fee is calculated by using the following formula: Hourly fee for backup storage = (Total size of backup files - Free quota) × Unit price of storage.

Usage notes

• The backup storage fee varies based on the total size of backup files. Backup files do not consume the storage capacity of your RDS instance. Therefore, the backup storage fee is not affected by the storage usage.

• When you analyze the backup storage fee, you must check the total size of backup files. You do not need to check the storage usage.

• Management operations that involves the change of cloud disks, such as the re-creation of a secondary RDS instance, have the following impacts on an RDS instance that uses cloud disks:

  • The backup storage of the RDS instance that uses cloud disks increases. As a result, the backup storage fees increase. The code of the billable item is BackupCharged.

  • The traffic consumed by cross-region backups of the RDS instance that uses cloud disks increases. As a result, the traffic fees of cross-region backups increase. The code of the billable item is NetworkOutDuplicationSize.

  • The cross-region backup storage of the RDS instance that uses cloud disks increases. As a result, the fees generated for cross-region backup storage increase. The code of the billable item is BackupStorageSize.

  Note

  For example, if you perform a DDL operation on an RDS instance that uses cloud disks and the operation causes the latency of data replication to the secondary RDS instance of the RDS instance to be longer, the system may automatically re-create the secondary RDS instance to ensure service stability. This increases the fees for the preceding billable items.

Methods to reduce the backup storage fee

• Reduce the total size of backup files.

  You can delete the backup files that are no longer required. You can also reduce the backup frequency. For more information, see View and manage the size of backup files.

• Increase the free quota.

  You can expand the storage capacity of your RDS instance. For more information, see Change instance specifications.

  The free quota varies based on the storage capacity of your RDS instance. If your RDS instance uses local disks and you expand the storage capacity of your RDS instance from 150 GB to 300 GB, the free quota is increased from 75 GB to 150 GB.

Billing FAQ

• Can I disable the backup feature of my RDS instance to stop being charged if the size of the backup files that are automatically generated exceeds the free quota?

  The backup feature of RDS instances is enabled by default and cannot be disabled. However, you can modify the automatic backup strategies of your RDS instance to delete existing backup files or reduce the number of new backup files. For more information, see Delete backup files or reduce the size of backup files.

• Why am I charged for backup storage even if the total size of the backup files of my RDS instance does not exceed the free quota for backup storage?

  You are charged for backup storage because the size of the backup files exceeded the free quota in the past, and the system does not deduct the additional fee at the earliest opportunity.

• Why is the size of backup files larger than the amount of data on my RDS instance?

  The size of backup files may not equal the amount of data on your RDS instance.

  If your RDS instance uses cloud disks, the system creates snapshots to back up your RDS instance. The size of a snapshot backup file may be significantly larger than the amount of data. The free quota on backup storage for an RDS instance that uses cloud disks is 200% of the storage capacity of the RDS instance. The free quota on backup storage for an RDS instance that uses local disks is 50% of the storage capacity of the RDS instance.

  Note

  When the system calculates the size of a snapshot backup file, the system counts in all the non-empty blocks to which data is written. If the write operations are scattered among blocks, none of the blocks is empty. For example, if 3 MB of data is written across two, three, or four blocks, none of these blocks is empty. In this case, the system counts in all these blocks to calculate the total size. As a result, the size of the snapshot backup file is larger than the actual amount of data.

• The backup retention period of my RDS instance is shortened from x days to y days. Why does the size of backup files remain unchanged?

  If no backup files are retained for more than y days, no backup files are deleted and the size of backup files remains unchanged after you shorten the backup retention period.