This topic describes how to change the specifications of your cluster to meet business requirements.

ApsaraDB for PolarDB supports capacity scaling in three dimensions:

  • Vertical scaling of computing power

    You can upgrade or downgrade the specifications of a cluster. This topic describes the details.

  • Horizontal scaling of computing power

    You can add or delete read-only nodes. For more information, see Add or remove a read-only node.

  • Horizontal scaling of storage capacity

    The storage capacity is provisioned in a serverless model. As your data increases in size, the storage is automatically expanded.

You can upgrade or downgrade the specifications of an ApsaraDB for PolarDB cluster. It takes only 5 minutes to 10 minutes for the new specifications of each node to take effect.

Specification change fees

For more information, see Configuration change fees.


You can only change cluster specifications when the cluster does not have pending specification changes.


  • Specification upgrades or downgrades only apply to clusters. You cannot change the specifications of a node.
  • Specification upgrades or downgrades do not affect the existing data in the cluster.
  • We recommend that you modify cluster specifications during off-peak periods. During a specification upgrade or downgrade, the ApsaraDB for PolarDB service will be disconnected for a few seconds and some of the functions will be disabled. You will need to reconnect from your applications after the service is disconnected.


  1. Log on to the ApsaraDB for PolarDB console.
  2. In the upper-left corner of the page, select the region.
  3. Go to the Change Configurations page. Perform the operation by using either of the following methods:
    • Find the target cluster and click Change Configurations in the Actions column corresponding to the target cluster.Change Configurations
    • Find the target cluster, click the cluster ID, and then click Change Configurations in the Node Information section.Change Configurations
  4. Select Upgrade or Downgrade and click OK. Change Configuration (Subscription)
  5. Select a specification.
    Note All nodes in a cluster have the same specifications.
  6. Read and agree to the service agreement by selecting the check box, and click Pay to complete the payment.
    Note It takes about ten minutes for the new specifications to take effect.

Related API operations

API Description
ModifyDBNodeClass Changes the specifications of a PolarDB cluster.