Help Center/ GeminiDB/ GeminiDB DynamoDB-Compatible API/ Working with GeminiDB DynamoDB-Compatible API/ Instance Modifications/ Scaling Storage Space/ Manually Scaling Down Storage of a GeminiDB DynamoDB-Compatible Instance
Updated on 2026-07-10 GMT+08:00
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Manually Scaling Down Storage of a GeminiDB DynamoDB-Compatible Instance

Scenarios

After peak hours, if the storage usage of a DB instance continues to decrease, scaling down storage can release unused space, reclaim resources, and reduce costs.

Usage Notes

Deployment Type

Description

Classic
  • The target storage after scale-down must exceed 125% of the used storage. The value is rounded up.
  • Select at least 1 GB each time, and the value must be an integer.
  • You do not need to restart the instance while scaling its storage. The change has no impact on existing data, services, or your databases.
  • If your yearly/monthly instance is running out of storage, additional usage will be billed on a pay-per-use basis. To avoid these extra costs and maintain the benefits of your yearly/monthly subscription, you are advised to scale up storage.

Cloud native
  • The target storage after scale-down must exceed 125% of the used storage. The value is rounded up.
  • Select at least 100 GB each time, and the value must be an integer multiple of 10.
  • During the scale-down, the instance will be restarted intermittently, which may cause slight performance fluctuation. Data migration may take hours or even days, depending on the total data volume and node configurations. You are advised to perform the scale-down during off-peak hours.
  • The new storage allocation takes effect as soon as the scale-down is completed. Before proceeding, ensure that data growth is minimal, no burst traffic is anticipated, and all required data has been backed up.
  • This function has specific requirements on underlying hardware resources and is only available for certain instance specifications. To check whether your instance supports this function, submit a service ticket on the console to contact the customer service.

Billing

Table 1 Billing

Billing Mode

Operation

Impact on Price

Yearly/Monthly

Storage scale-down

After the scale-down, the new storage takes effect for the remaining subscription period. As the new configuration costs less than the previous one, Huawei Cloud will refund you the price difference.

Example (The specifications and prices below are for reference only. The actual prices are displayed on the console.)

Assume that you purchased a yearly/monthly DynamoDB-Compatible instance with 80 GB of storage for one month on April 8, 2023, at a unit storage price of $1 USD/GB/month. On April 18, 2023, you reduced 40 GB of storage, bringing the total to 40 GB. The price difference is calculated as follows:

Refund amount = Reduced storage × Unit price × Remaining period

The remaining period in the formula is calculated by dividing remaining days in each calendar month by the total days in that month. In this example, the remaining period is 0.6581 [12 (remaining days in April)/30 (total days in April) + 8 (remaining days in May)/31 (total days in May)]. The refund amount is therefore $26.3 USD (40 × 1 × 0.6581).

For details, see Yearly/Monthly Billing.

Pay-per-use

Storage scale-down

After storage is scaled down, a new order is generated and you will be billed at the new price. The old order is automatically invalidated.

For details, see Pay-per-use Billing.

About Read-Only Instances

To maintain instance stability, the system checks its storage every 10 seconds. If your GeminiDB DynamoDB-Compatible instance is running out of storage, it will become read-only and its data cannot be modified. If this happens, you can scale up the storage to restore the instance status.

Table 2 describes the read-only status of instances with cloud native storage.
Table 2 Read-only status of instances with cloud native storage

Storage

Description

< 16,000 GB
  • When the storage usage reaches 97%, the instance becomes read-only.
  • When the storage usage decreases to 85%, the instance exits the read-only mode.

≥ 16,000 GB
  • If the remaining storage is less than 480 GB, the instance becomes read-only.
  • When the remaining storage is greater than or equal to 2400 GB, the instance exits the read-only mode.

Instances with classic storage do not support read-only mode.

Procedure

  1. Log in to the Huawei Cloud console.
  2. On the Instances page, locate the target instance and choose More > Scale Storage Space in the Operation column.

    Click the instance name. In the Storage Space area on the Basic Information page, click Scale.

  3. On the displayed page, specify new storage and click Next.

    Figure 1 Scaling down storage space
    • To scale down classic storage, you need to select at least 1 GB each time. The value must be an integer.
    • To scale down cloud native storage, you need to select at least 100 GB each time. The value must be an integer multiple of 10.

  4. On the displayed page, confirm the storage space.

    • Yearly/Monthly
      • To modify your settings, click Previous to go back to the page where you specify details.
      • If you do not need to modify your settings, click Next and complete the payment.
    • Pay-per-use
      • To modify your settings, click Previous to go back to the page where you specify details.
      • If you do not need to modify your settings, click Submit.

  5. Check the results.

    • During the scale-down process, the instance status becomes Scaling storage space.
    • After the scaling process, the instance status becomes Available.
    • Click the instance name. In the Storage Space area on the Basic Information page, check the new storage space.

Parent Topic: Scaling Storage Space