This topic describes how to configure automatic storage expansion for an ApsaraDB RDS for PostgreSQL instance.
Prerequisites
The RDS instance uses cloud disks and is in the Running state.
The balance in your Alibaba Cloud account is sufficient for the expansion.
Usage notes
You can use the WAL log management feature to check whether redundant replication slots exist. You can manually delete inactive replication slots to allow AliPG to automatically delete WAL logs. Then, check whether the storage capacity meets your business requirements. If the storage capacity cannot meet your business requirements, configure automatic storage expansion. For more information about WAL log management, see Use the WAL log management feature for an ApsaraDB RDS for PostgreSQL instance.
Starting February 28, 2023, optimizations of the rules for automatic storage expansion are rolled out in different regions. If your RDS instance is a primary RDS instance and has read-only RDS instances, the system checks the storage capacity of each read-only instance when automatic storage expansion is triggered for the primary instance. If the storage capacity of a read-only instance is less than the required storage capacity of the primary instance after expansion, the system preferentially expands the storage capacity of the read-only instance. After the storage capacity of each read-only RDS instance is expanded, the system automatically expands the storage capacity of the primary RDS instance. For more information, see [Product changes/Feature changes] Optimization of automatic storage expansion for ApsaraDB RDS for MySQL instances and ApsaraDB RDS for PostgreSQL instances.
If the RDS instance is being backed up, you can start the automatic storage expansion task after the backup is complete.
Billing rules
The billing rules for automatic storage expansion are the same as the billing rules for manual storage expansion of an RDS instance. For more information, see Specification change fees.
Procedure
- Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.
In the Usage Statistics section of the page that appears, click Settings on the right of Automatic Storage Expansion.
Configure the following parameters.
Parameter
Description
Automatic Storage Expansion
The switch that is used to enable or disable automatic storage expansion.
Available Storage ≤
The threshold based on which automatic storage expansion is triggered. The threshold is expressed as a percentage. If the available storage reaches the threshold, the system expands the storage capacity of the RDS instance.
NoteThe amount of storage that you can increase is the larger value of the following values:
5 GB. If the storage capacity of the RDS instance is less than 50 GB and the percentage of the available storage is less than 10% of the storage capacity, the step size for storage capacity expansion is adjusted to 10 GB.
15% of the current storage capacity of the RDS instance. The result is the nearest integer that is a multiple of 5.
Maximum Storage Capacity
The maximum storage capacity that is allowed by automatic storage expansion. The value of this parameter must be greater than or equal to the current storage capacity of the RDS instance.
If the RDS instance uses Enterprise SSDs (ESSDs), you can set this parameter to 32,000 GB.
If the RDS instance uses SSDs, the maximum value of this parameter can be set to 6,000 GB.
Click OK.
View a storage expansion record
- Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.
In the Usage Statistics section, click Storage Expansion Records on the right of Automatic Storage Expansion to go to the Database Autonomy Service (DAS) console.
On the Autonomy Center page, set the Type parameter to Auto-Scaling Events to view the storage expansion records.
Click Details of the required scaling event to view the details of the storage expansion record.
Related operations
Operation | Description |
Configures automatic storage expansion for an instance. |