This topic provides answers to frequently asked questions about the pricing of scale-out and scale-in of PolarDB clusters.
- What is the price if I add a read-only node?
The price of a read-only node is the same as that of a primary node. For more information, see Pricing of compute nodes.
- Is the storage capacity doubled after I add a read-only node?
No, the storage capacity is not doubled after you add a read-only node. PolarDB uses an architecture in which computing is decoupled from storage. The read-only node that you purchase is used as a computing resource. Therefore, the storage capacity is not increased.
A serverless architecture is used for storage. Therefore, you do not need to specify the storage capacity when you purchase clusters. The storage capacity is automatically scaled out when the amount of data increases. You are charged only for the storage that you use. Each type of cluster specifications has the corresponding maximum storage capacity. To increase the maximum storage capacity, Change the specifications of a cluster.