This topic lists the limits of Resource Orchestration Service (ROS).
| Item | Limit |
|---|---|
| The maximum number of stacks allowed to be created by an Alibaba Cloud account. | 200 |
| The maximum number of templates allowed to be created by an Alibaba Cloud account. | 100 |
| The maximum number of stack groups allowed to be created by an Alibaba Cloud account. | 100 |
| The maximum number of instances allowed to be created in a stack group by an Alibaba Cloud account. | 2,000 |
| The maximum number of concurrent operations allowed to be performed on stack groups within a region by an Alibaba Cloud account. | 3,500 |
| The maximum number of change sets allowed to be created in a stack by an Alibaba Cloud account. | 20 |
| The maximum number of resources allowed to be created in a stack. | 200 |
| The maximum number of levels that a nested stack is allowed to contain. | 5 |
| The maximum timeout period of a stack. | 1,440 minutes (or 24 hours) |
| The minimum timeout period of a stack. | 10 minutes |
| The maximum size of a template file. | 512KB |
| The maximum size of a custom resource response. | 4,096KB |
| The maximum size of a change set file. | 2,048KB |
| The maximum size of a stack policy file. | 16KB |