This topic describes how to upgrade or downgrade the specifications of a PolarDB cluster. It takes only 5 to 10 minutes for the new specifications of each node to take effect.


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

Background information

This topic describes how to change the specifications of a cluster to meet your business requirements. PolarDB supports capacity scaling in three dimensions:

  • Vertically scale the computing capacity: Upgrade or downgrade the specifications of the cluster. This topic describes the details of vertically scaling.
  • Horizontal scaling of computing capabilities: Add or remove 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. The storage capacity is automatically scaled based on the amount of data.

Configuration change fees

For more information, see Configuration change fees.


  • You can upgrade or downgrade only clusters. You cannot upgrade or downgrade a single node in a cluster.
  • When you upgrade or downgrade a cluster, data stored in the cluster is not affected.
  • During the upgrade or downgrade process, your applications are temporarily disconnected from each endpoint for no more than 30 seconds. We recommend that you upgrade or downgrade your cluster during off-peak hours and make sure that your applications are configured with the automatic reconnection mechanism.


  1. Log on to the PolarDB console.
  2. In the upper-left corner of the console, select the region in which the cluster that you want to manage is deployed.
  3. Go to the Change Configurations page by using one of the following two methods:
    • Find the cluster whose specifications you want to change, and click Change Configurations in the Actions column. Cluster list
    • Click the ID of the cluster whose specifications you want to change. Then, in the Database Nodes section of the Overview page, click Change Configurations. Basic information
  4. Select Upgrade or Downgrade and click OK. Change configurations
    Note Only subscription clusters support Temporary Upgrade. For more information, see Perform a temporary cluster upgrade.
  5. Select the desired specifications and switching time.
    Note All nodes in a cluster must use the same specifications.
  6. Read and agree to the terms of the service. Then, click Buy Now and complete the payment.
    Note The new specifications take effect within 10 minutes.

Related API operations

Operation Description
ModifyDBNodeClass Changes the node specifications of a PolarDB cluster.