The prices of read-only ApsaraDB RDS for PostgreSQL instances that use standard SSDs or enhanced SSDs (ESSDs) will be reduced since April 12, 2022.

Effective time

April 12, 2022

Price reductions

  • The prices of subscription read-only RDS instances are reduced by approximately 45%.
  • The prices of pay-as-you-go read-only RDS instances are reduced by approximately 17%.
Note For example, before April 12, 2022, the price of a subscription read-only RDS instance is USD 100 per month. Since April 12, 2022, the price of the instance is approximately USD 55 per month based on the following calculation: 100 × (1 - 45%) = 55.

Introduction to read-only RDS instances

To offload read requests from the primary RDS instance, you can create one or more read-only RDS instances. Read-only RDS instances help increase the read capability of your database system and the throughput of your application.

When a read-only RDS instance is being created, ApsaraDB RDS replicates data from the secondary RDS instance to the read-only RDS instance. After the read-only RDS instance is created, it has the same data as the primary RDS instance. In addition, after the data on the primary RDS instance is updated, ApsaraDB RDS immediately synchronizes the updates to all read-only RDS instances that are attached to the primary RDS instance.

The following figure shows the topology of the primary RDS instance and its read-only RDS instances. PostgreSQL topology

Purchase read-only RDS instances

For more information about how to create a read-only RDS instance, see Create a read-only ApsaraDB RDS for PostgreSQL instance.