PolarDB for MySQL supports three billing methods: subscription, pay-as-you-go, and serverless. Use the table below to match your workload pattern to the right method.
Choose a billing method
| Billing method | Best for | Payment | Compute nodes | Billing cycle | Switch to |
|---|---|---|---|---|---|
| Subscription | Stable, predictable workloads with a known usage duration | Upfront | Defined specifications | Based on the Duration you select | Pay-as-you-go |
| Pay-as-you-go | Unpredictable or short-term workloads | Post-paid | Defined specifications | Per second, billed hourly | Subscription |
| Serverless | Fluctuating or unpredictable workloads; individual developers; development and staging environments; IoT and edge computing | Post-paid | Dynamic (scales automatically in PolarDB Capacity Units, or PCUs) | Per second, billed hourly | Not supported |
Some billable items support only the pay-as-you-go billing method. For details, see Billable items. Switch rules vary by edition. For details, see Switch billing methods.
Serverless billing unit: A PolarDB Capacity Unit (PCU) is the billing unit for serverless clusters. Serverless clusters are billed per second based on the average number of PCUs consumed. For the full pricing formula, see Billing rules for serverless compute nodes.
Combination with resource plans (recommended)
Subscription
Serverless compute plans
If you enable the serverless feature for your cluster with defined specifications, you can use a serverless compute plan to offset the costs of dynamic resources on compute nodes. For more information, see Enable the serverless feature for a cluster with defined specifications.
You can also refer to the following scenarios and benefits to evaluate whether to use a serverless compute plan.
Category
Description
Object to offset
Dynamic resources of compute nodes.
Scenarios
Frequent workload fluctuations
For scenarios with significant workload fluctuations, to offset the cost of dynamic resources required when the workload exceeds the defined specifications.
Multiple clusters
You have multiple clusters that meet the deduction rules of the Serverless compute plan.
NoteDynamic resources for compute nodes can be generated by enabling the serverless feature for a cluster with defined specifications or by a serverless cluster.
Benefits
Wide deduction scope
Deductions are not applied on a per-cluster basis. Instead, they apply to all clusters under your Alibaba Cloud account across all regions that meet the deduction rules of the serverless compute plan.
Best practices
How to estimate the required specifications for a Serverless compute plan.
Storage plans
Pay-as-you-go
Compute plans for defined specifications
If the serverless feature is not enabled for your cluster with defined specifications, the compute nodes use resources with defined specifications. In this case, you can use a compute plan for defined specifications to offset the costs of these resources. You can also refer to the following scenarios and benefits to evaluate whether to use this type of compute plan.
Category
Description
Object to offset
Defined specification resources of compute nodes.
Scenarios
Frequent workload fluctuations
You may need to change the cluster configuration monthly or even weekly. When the cluster configuration is adjusted, the compute plan for defined specifications can automatically apply deductions based on the current specifications.
Multiple clusters
You have multiple clusters that meet the deduction rules of the compute plan for defined specifications.
Example scenario 1
During product selection, you need to perform proof of concept (POC) tests on various cluster specifications, but the testing costs are relatively high.
First, purchase a compute plan for defined specifications. Then, purchase pay-as-you-go clusters with different specifications for testing. The costs of resources with defined specifications for compute nodes in all PolarDB for MySQL, , and clusters can be offset by the compute plan.
Example scenario 2
During school training, you need to purchase multiple clusters for demos and learning, and the subscription method is not cost-effective.
The school can purchase a single compute plan for defined specifications. Students can then create multiple pay-as-you-go clusters and release them immediately after use. This method is not only flexible and convenient but also more cost-effective than using the regular pay-as-you-go billing method.
Example scenario 3
If your workload fluctuates significantly and frequently, you can use a compute plan for defined specifications together with the Database Autonomy Service (DAS).
After purchasing a compute plan for defined specifications, you can enable the automatic scaling feature for your pay-as-you-go cluster. When the cluster configuration is adjusted, the compute plan automatically applies deductions based on the current specifications.
Benefits
Low price
The cost of [Pay-as-you-go + Compute plan for defined specifications] is 35% to 56% lower than pay-as-you-go alone, making it more cost-effective. You can receive different discounts based on the capacity of the compute plan you purchase.
Flexible
Pay-as-you-go clusters can be purchased, upgraded, and released at any time, providing flexibility and convenience.
Wide deduction scope
Deductions are not applied on a per-cluster basis. Instead, they apply to all clusters under your Alibaba Cloud account across all regions that meet the deduction rules of the compute plan for defined specifications.
Best practices
How to estimate the required specifications for a compute plan for defined specifications.
Serverless compute plans
If you enable the serverless feature for your cluster with defined specifications, you can use a serverless compute plan to offset the costs of dynamic resources on compute nodes. For more information, see Enable the serverless feature for a cluster with defined specifications.
You can also refer to the following scenarios and benefits to evaluate whether to use a serverless compute plan.
Category
Description
Object to offset
Dynamic resources of compute nodes.
Scenarios
Frequent workload fluctuations
For scenarios with significant workload fluctuations, to offset the cost of dynamic resources required when the workload exceeds the defined specifications.
Multiple clusters
You have multiple clusters that meet the deduction rules of the Serverless compute plan.
NoteDynamic resources for compute nodes can be generated by enabling the serverless feature for a cluster with defined specifications or by a serverless cluster.
Benefits
Wide deduction scope
Deductions are not applied on a per-cluster basis. Instead, they apply to all clusters under your Alibaba Cloud account across all regions that meet the deduction rules of the serverless compute plan.
Best practices
How to estimate the required specifications for a Serverless compute plan.
Storage plans
Serverless
Serverless compute plans
The compute nodes of a serverless cluster use dynamic resources. You can use a serverless compute plan to offset the costs of these dynamic resources. You can also refer to the following scenarios and benefits to evaluate whether to use a serverless compute plan.
Category
Description
Object to offset
Dynamic resources of compute nodes.
Scenarios
Frequent workload fluctuations
For scenarios with significant workload fluctuations, to offset the cost of dynamic resources required when the workload exceeds the defined specifications.
Multiple clusters
You have multiple clusters that meet the deduction rules of the Serverless compute plan.
NoteDynamic resources for compute nodes can be generated by enabling the serverless feature for a cluster with defined specifications or by a serverless cluster.
Benefits
Wide deduction scope
Deductions are not applied on a per-cluster basis. Instead, they apply to all clusters under your Alibaba Cloud account across all regions that meet the deduction rules of the serverless compute plan.
Best practices
How to estimate the required specifications for a Serverless compute plan.
Storage plans
Configuration changes
When you change a cluster's configuration, charges adjust based on the billing method. For details, see Change configurations.
| Billing method | How charges adjust |
|---|---|
| Subscription | Upgrades and added nodes incur additional fees. Downgrades and deleted nodes generate a refund. |
| Pay-as-you-go | After you change the configuration, you are charged hourly based on the price of the new configuration. |
| Serverless | Configuration changes are not supported. Compute resources scale automatically based on the service payload. |
Expiration and overdue payments
Service interruptions may occur when a subscription cluster expires or a payment becomes overdue. The system sends a notification for both events. To prevent interruptions, add funds to your Alibaba Cloud account or renew the cluster immediately. For details, see Expiration and overdue payments.