RDS for PostgreSQL Product Series
RDS for PostgreSQL DB instances are classified into the following types:
- Single
- Primary/Standby
DB Instance Type | Description | Notes | Advantages | Scenarios |
---|---|---|---|---|
Single | A single-node architecture is more cost-effective than a primary/standby DB pair. | If the node fails, the restoration will take a long time. Therefore, single-node instances are not recommended for sensitive workloads that have high requirements on database availability. | Different from primary/standby instances that have two database nodes, a single-node instance has only one node and can reduce costs. |
|
Primary/Standby | An HA architecture. A pair of primary and standby DB instances shares the same IP address and can be deployed in different AZs. |
| An HA architecture improves database reliability. If the primary node fails, the standby node attempts to become the primary node to reduce the impact on workloads. |
|
Advantage Comparison
- Single DB instances: support the creation of read replicas and support the queries of error logs and slow query logs. Different from primary/standby DB instances that have two database nodes, a single DB instance has only one node. If the node fails, the restoration will take a long time. Therefore, single DB instances are not recommended for sensitive services that have high requirements on database availability.
- Primary/Standby DB instances: use the standby database node only for failover and restoration. The standby database node does not provide services. The performance of single DB instances is similar to or even higher than primary/standby DB instances because standby nodes cause extra performance overhead.
Function | Single | Primary/Standby |
---|---|---|
Number of nodes | 1 | 2 |
Specifications | vCPUs: a maximum of 60 Memory: a maximum of 512 GB Storage: a maximum of 4,000 GB | vCPUs: a maximum of 60 Memory: a maximum of 512 GB Storage: a maximum of 4,000 GB |
Monitoring and alarms | Supported | Supported |
Security group | Supported | Supported |
Backup and restoration | Supported | Supported |
Parameter settings | Supported | Supported |
SSL | Supported | Supported |
Log management | Supported | Supported |
Read replicas (which need to be created) | Supported | Supported |
High-frequency monitoring | Supported | Supported |
Failover | Not supported | Supported |
Standby DB instance migration | Not supported | Supported |
Manual primary/standby switchover | Not supported | Supported |
Instance class change | Supported | Supported |
- Advantage Comparison