PolarDB allows you to use the backup and restoration features free of charge. However, backup files consume storage space. This topic describes the billing rules of storage space consumed by PolarDB backup files.

Free quota

PolarDB offers a free storage quota for backup files. After this quota is consumed, you are charged by PolarDB for additional storage space occupied by backup files and the length of time for which the files are retained.

Backup type Free quota
Data backup Level-1 backup Database storage usage × 50%

For more information about how to view the database storage usage, see View the database storage usage.

Level-2 backup None
Log backup 100 GB

Pay-as-you-go

After the free quota is consumed, you are charged for additional storage space consumed by backup files and the length of time for which the files are retained.

Backup type Unit price (USD/GB/hour) Billing method
Regions inside mainland China The China (Hong Kong) region and regions outside China
Level-1 backup

0.000464

0.000650

Storage fee per hour = (Total size of level-1 backups - Free quota) × Unit price per hour

For example, if the total size of level-1 backups (snapshots) is 700 GB and the database storage usage is 1,000 GB, the storage fee per hour is USD 0.0928.

The fee is calculated based on the following formula: [700 GB - (1,000 GB × 50%)] × USD 0.000464/GB/hour = USD 0.0928/hour.

Note For more information, see FAQ.
Level-2 backup

0.0000325

0.0000455

Storage fee per hour = Total size of level-2 backups × Unit price per hour

For example, if the total size of level-2 backups is 1,000 GB, the storage fee per hour is USD 0.0325.

The fee is calculated based on the following formula: 1,000 GB × USD 0.0000325/GB/hour = USD 0.0325/hour.

Log backup

0.0000325

0.0000455

Storage fee per hour = (Total size of log backups - 100 GB) × Unit price per hour

For example, if the total size of log backups is 1,000 GB, the hourly fee is USD 0.02925.

The fee is calculated based on the following formula: (1,000 GB - 100 GB) × USD 0.0000325/GB/hour = USD 0.02925/hour.

Use storage plans to offset level-1 backup storage fees

After the free quota is consumed, you are charged for additional storage space on a pay-as-you-go basis. To reduce the costs of level-1 backups, we recommend that you use storage plans, which are cost-effective.

Storage plans are applied to all PolarDB clusters that belong to your account. The remaining capacity of a storage plan is automatically used to offset the level-1 backup storage space that exceeds the free quota at a ratio of 1:1.6. In this case, every 1 GB of the storage plan is used to offset 1.6 GB of level-1 backup storage.

For example, you purchase a storage plan of 100 GB in size and you have 50 GB of data. The data itself consumes 50 GB of the storage plan, which leaves 50 GB remaining. The level-1 backups of the cluster consume 50 GB of storage space beyond the free quota. In this case, 31.25 GB (50/1.6 = 31.25) of the storage plan is automatically used to offset the additional storage space consumed by the level-1 backups, which leaves a final size of 18.75 GB remaining in your storage plan.

If the remaining capacity of the storage plan is insufficient to offset the level-1 backup storage space, you are charged for additional storage space on a pay-as-you-go basis. For more information about storage plans, see Storage plans.