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.
Note
Some instance type options do not support this capability. For more information, see Supported CPU options in the Amazon EC2 User Guide.
Request Parameters
The following parameters are for this specific action. For more information about required and optional parameters that are common to all actions, see Common Query Parameters.
- CoreCount
-
The number of CPU cores to activate for the specified instance.
Type: Integer
Required: Yes
- DryRun
-
Checks whether you have the required permissions for the operation, without actually making the request, and provides an error response. If you have the required permissions, the error response is
DryRunOperation. Otherwise, it isUnauthorizedOperation.Type: Boolean
Required: No
- InstanceId
-
The ID of the instance to update.
Type: String
Required: Yes
- ThreadsPerCore
-
The number of threads to run for each CPU core.
Type: Integer
Required: Yes
Response Elements
The following elements are returned by the service.
- coreCount
-
The number of CPU cores that are running for the specified instance after the update.
Type: Integer
- instanceId
-
The ID of the instance that was updated.
Type: String
- requestId
-
The ID of the request.
Type: String
- threadsPerCore
-
The number of threads that are running per CPU core for the specified instance after the update.
Type: Integer
Errors
For information about the errors that are common to all actions, see Common client error codes.
Examples
Example
This request example modifies the number of active vCPUs for the specified
instance in the specified Region to 4 CPU cores running 2
threads each. This example assumes that the instance was stopped prior to running the
request.
Sample Request
https://ec2.amazonaws.com/?Action=ModifyInstanceCpuOptions
&Region=us-east-1
&InstanceId=i-1234567890abcdef0
&CoreCount=4
&ThreadsPerCore=2
&AUTHPARAMSSample Response
<ModifyInstanceCpuOptionsResponse xmlns="http://ec2.amazonaws.com/doc/2016-11-15/">
<requestId>11111111-2222-3333-4444-5555EXAMPLE</requestId>
<instanceId>i-1234567890abcdef0</instanceId>
<coreCount/>4</coreCount/>
<threadsPerCore/>2</coreCount/>
</ModifyInstanceCpuOptionsResponse>See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following:
