# Setting the CPU cores and threads per CPU core for a DB instance class You can configure the number of CPU cores and threads per core for the DB instance class when you perform the following operations: + [Creating an Amazon RDS DB instance](USER_CreateDBInstance.md) + [Modifying an Amazon RDS DB instance](Overview.DBInstance.Modifying.md) + [Restoring to a DB instance](USER_RestoreFromSnapshot.md) + [Restoring a DB instance to a specified time for Amazon RDS](USER_PIT.md) **Note** When you modify a DB instance to configure the number of CPU cores or threads per core, there is a brief outage similar to when you modify the instance class. Set the CPU cores by using the AWS Management Console, the [AWS CLI](https://aws.amazon.com/cli/), [AWS Tools for PowerShell](https://aws.amazon.com/powershell/), or the [Amazon RDS API](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/Welcome.html). The AWS CLI and AWS Tools for PowerShell come preinstalled in [AWS CloudShell](https://aws.amazon.com/cloudshell/). The Optimize CPU settings are the [ProcessorFeature](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_ProcessorFeature.html) values `coreCount` and `threadsPerCore`. The processor feature values are `null` if Optimize CPU is not configured. ## Console **To set the processor features when you create a DB instance** 1. Sign in to the AWS Management Console and open the Amazon RDS console at [https://console.aws.amazon.com/rds/](https://console.aws.amazon.com/rds/). 1. Choose **Create database**. 1. When setting the **Instance configuration** options: 1. Under **Optimize CPU**, select **Configure the number of vCPUs**. 1. Under **vCPUs**, choose the number of **thread(s) per CPU core** and the number of **core(s)**. The lists show the valid values for the selected instance class. For more information, see [DB instance classes that support Optimize CPU](SQLServer.Concepts.General.OptimizeCPU.Support.md). ![Database create page when setting OCPU settings.](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/images/OCPU-screenshot.png) 1. After completing other selections, choose **Create database**. **To view the processor features of a DB instance** 1. Sign in to the AWS Management Console and open the Amazon RDS console at [https://console.aws.amazon.com/rds/](https://console.aws.amazon.com/rds/). 1. In the navigation pane, choose **Databases**, and then choose the DB instance. 1. Choose the **Configuration** tab. 1. Under **Processor Features**, view the **vCPU**, **Core count**, and **Threads per core** values. **To modify the processor features of a DB instance** 1. Sign in to the AWS Management Console and open the Amazon RDS console at [https://console.aws.amazon.com/rds/](https://console.aws.amazon.com/rds/). 1. In the navigation pane, choose **Databases**, and then choose the DB instance that you want to modify. 1. Choose **Modify**. 1. For **Optimize CPU**, choose **Configure the number of vCPUs**. 1. Under **vCPUs**, choose the number of **thread(s) per CPU core** and the number of **core(s)**. The lists show the valid values for the selected instance class. For more information, see [DB instance classes that support Optimize CPU](SQLServer.Concepts.General.OptimizeCPU.Support.md). 1. Choose **Continue**. 1. For **When to apply modifications**, choose **Apply during the next scheduled maintenance window** or **Apply immediately**. 1. Choose **Modify DB instance**. **To return a DB instance to the default processor features** 1. Sign in to the AWS Management Console and open the Amazon RDS console at [https://console.aws.amazon.com/rds/](https://console.aws.amazon.com/rds/). 1. In the navigation pane, choose **Databases**, and then choose the DB instance that you want to modify. 1. Choose **Modify**. 1. For **Optimize CPU**, choose **Use default vCPUs**. 1. Choose **Continue**. 1. For **When to apply modifications**, choose **Apply during the next scheduled maintenance window** or **Apply immediately**. 1. Choose **Modify DB instance**. ## AWS CLI **To set the processor features when you create a DB instance** 1. To configure Optimize CPU using the AWS CLI, include the `--processor-features` option in the [create-db-instance](https://docs.aws.amazon.com/cli/latest/reference/rds/create-db-instance.html) command. Specify the number of CPU cores with the `coreCount` and `threadsPerCore` as `1`. 1. Use the following syntax: ``` aws rds create-db-instance \ --db-instance-identifier {{my-rds-instance}} \ --engine sqlserver-ee \ --engine-version 17.00 \ --license-model license-included \ --db-instance-class db.r8i.8xlarge \ --allocated-storage 300 \ --master-username {{admin}} \ --manage-master-user-password \ --no-multi-az \ --vpc-security-group-ids {{sg-0123456789abcdef0}} \ --db-subnet-group-name {{mydbsubnetgroup}} \ --processor-features "Name=coreCount,Value={{12}}" "Name=threadsPerCore,Value=1" ``` **Example of viewing valid processor features for a DB instance class** Use the [describe-orderable-db-instance-options](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-orderable-db-instance-options.html) command to show the default and allowed values. ``` aws rds describe-orderable-db-instance-options \ --engine sqlserver-ee \ --db-instance-class db.r8i.8xlarge \ --query "OrderableDBInstanceOptions[0].AvailableProcessorFeatures" ``` In addition, you can run the following commands for DB instance class processor information: + [describe-db-instances](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-db-instances.html) – Shows the processor information for the specified DB instance + [describe-db-snapshots](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-db-snapshots.html) – Shows the processor information for the specified DB snapshot + [describe-valid-db-instance-modifications](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-valid-db-instance-modifications.html) – Shows the valid modifications to the processor for the specified DB instance **Example of setting the number of CPU cores for a DB instance** The following example uses the [modify-db-instance](https://docs.aws.amazon.com/cli/latest/reference/rds/modify-db-instance.html) command to modify {{my-rds-instance}} by setting the number of CPU cores to 12 and threadsPerCore to 1. Apply the changes immediately by using `--apply-immediately`. If you want to apply the changes during the next scheduled maintenance window, omit the `--apply-immediately` option. ``` aws rds modify-db-instance \ --db-instance-identifier {{my-rds-instance}} \ --processor-features "Name=coreCount,Value={{12}}" "Name=threadsPerCore,Value=1" \ --apply-immediately ``` **Example of returning to default processor features for a DB instance** The following example uses the [modify-db-instance](https://docs.aws.amazon.com/cli/latest/reference/rds/modify-db-instance.html) command to modify {{my-rds-instance}} by returning it to the default processor features. ``` aws rds modify-db-instance \ --db-instance-identifier {{my-rds-instance}} \ --use-default-processor-features \ --apply-immediately ``` ## PowerShell **To set the processor features when you create a DB instance** 1. To configure Optimize CPU using AWS Tools for PowerShell, include the `-ProcessorFeature` parameter in the [New-RDSDBInstance](https://docs.aws.amazon.com/powershell/latest/reference/items/New-RDSDBInstance.html) cmdlet. Specify the number of CPU cores with the `coreCount` and `threadsPerCore` as `1`. 1. Use the following syntax: ``` New-RDSDBInstance ` -DBInstanceIdentifier {{my-rds-instance}} ` -Engine sqlserver-ee ` -EngineVersion 17.00 ` -LicenseModel license-included ` -DBInstanceClass db.r8i.8xlarge ` -AllocatedStorage 300 ` -MasterUsername {{admin}} ` -ManageMasterUserPassword $true ` -MultiAZ $false ` -VpcSecurityGroupId {{sg-0123456789abcdef0}} ` -DBSubnetGroupName {{mydbsubnetgroup}} ` -ProcessorFeature @{Name='coreCount';Value='{{12}}'},@{Name='threadsPerCore';Value='1'} ``` **Example of viewing valid processor features for a DB instance class** Use the [Get-RDSOrderableDBInstanceOption](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-RDSOrderableDBInstanceOption.html) cmdlet to show the default and allowed values. ``` Get-RDSOrderableDBInstanceOption ` -Engine sqlserver-ee ` -DBInstanceClass db.r8i.8xlarge | Select-Object -First 1 -ExpandProperty AvailableProcessorFeatures ``` In addition, you can run the following cmdlets for DB instance class processor information: + [Get-RDSDBInstance](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-RDSDBInstance.html) – Shows the processor information for the specified DB instance + [Get-RDSDBSnapshot](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-RDSDBSnapshot.html) – Shows the processor information for the specified DB snapshot + [Get-RDSValidDBInstanceModification](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-RDSValidDBInstanceModification.html) – Shows the valid modifications to the processor for the specified DB instance **Example of setting the number of CPU cores for a DB instance** The following example uses AWS Tools for PowerShell and the [Edit-RDSDBInstance](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-RDSDBInstance.html) cmdlet to modify {{my-rds-instance}} by setting the number of CPU cores to 12 and threadsPerCore to 1. If you want to apply the changes during the next scheduled maintenance window, omit the `-ApplyImmediately` parameter. ``` Edit-RDSDBInstance ` -DBInstanceIdentifier {{my-rds-instance}} ` -ProcessorFeature @{Name='coreCount';Value='{{12}}'},@{Name='threadsPerCore';Value='1'} ` -ApplyImmediately $true ``` **Example of returning to default processor features for a DB instance** The following example uses AWS Tools for PowerShell and the [Edit-RDSDBInstance](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-RDSDBInstance.html) cmdlet to modify {{my-rds-instance}} by returning it to the default processor features. ``` Edit-RDSDBInstance ` -DBInstanceIdentifier {{my-rds-instance}} ` -UseDefaultProcessorFeature $true ` -ApplyImmediately $true ```