modifyInstanceCpuOptions (original) (raw)

By default, all vCPUs for the instance type are active when you launch an instance. When you configure the number of active vCPUs for the instance, it can help you save on licensing costs and optimize performance. The base cost of the instance remains unchanged.

The number of active vCPUs equals the number of threads per CPU core multiplied by the number of cores. The instance must be in a Stopped state before you make changes.

Some instance type options do not support this capability. For more information, see Supported CPU options in the Amazon EC2 User Guide.