Setting the CPU cores and threads per CPU core for a DB instance class - Amazon Relational Database Service
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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:

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 Amazon Web Services Management Console, Amazon CLI or the RDS API.

To set the cores

  1. Sign in to the Amazon Web Services Management Console and open the Amazon RDS console at https://console.amazonaws.cn/rds/.

  2. Choose Create database.

  3. When setting the Instance configuration options:

    1. Choose the Optimize CPU option.

    2. Set your vCPU option by choosing the number of cores.

    Database create page when setting OCPU settings

  4. After completing other selections, select Create database.

To set the cores

  1. To configure Optimize CPU using the AWS CLI, include the --processor-features option in the command. Specify the number of CPU cores with the coreCount and threadsPerCore as 1.

  2. Use the following syntax:

    aws rds create-db-instance \
    --engine sqlserver-ee \
    --engine-version 16.00 \
    --license-model license-included \
    --allocated-storage 300 \
    --master-username myuser \
    --master-user-password xxxxx \
    --no-multi-az \
    --vpc-security-group-ids myvpcsecuritygroup \
    --db-subnet-group-name mydbsubnetgroup \
    --db-instance-identifier my-rds-instance \
    --db-instance-class db.m7i.4xlarge \
    --processor-features "Name=coreCount,Value=6" "Name=threadsPerCore,Value=1"
Example of viewing valid processor values for a DB instance class

Use the describe-orderable-db-instance-options command to show the default vCPUs, cores, and threads per core. For example, the output for the following command shows the processor options for the db.r7i.2xlarge instance class.

aws rds describe-orderable-db-instance-options --engine sqlserver-ee \
--db-instance-class db.r7i.2xlarge

Sample output: 
-------------------------------------------------------------
|            DescribeOrderableDBInstanceOptions             |
+-----------------------------------------------------------+
||               OrderableDBInstanceOptions                ||
|+------------------------------------+--------------------+|
||  DBInstanceClass                   |  db.r7i.2xlarge    ||
||  Engine                            |  sqlserver-ee      ||
||  EngineVersion                     |  13.00.6300.2.v1   ||
||  LicenseModel                      |  license-included  ||
||  MaxIopsPerDbInstance              |                    ||
||  MaxIopsPerGib                     |                    ||
||  MaxStorageSize                    |  64000             ||
||  MinIopsPerDbInstance              |                    ||
||  MinIopsPerGib                     |                    ||
||  MinStorageSize                    |  20                ||
||  MultiAZCapable                    |  True              ||
||  OutpostCapable                    |  False             ||
||  ReadReplicaCapable                |  True              ||
||  StorageType                       |  gp2               ||
||  SupportsClusters                  |  False             ||
||  SupportsDedicatedLogVolume        |  False             ||
||  SupportsEnhancedMonitoring        |  True              ||
||  SupportsGlobalDatabases           |  False             ||
||  SupportsIAMDatabaseAuthentication |  False             ||
||  SupportsIops                      |  False             ||
||  SupportsKerberosAuthentication    |  True              ||
||  SupportsPerformanceInsights       |  True              ||
||  SupportsStorageAutoscaling        |  True              ||
||  SupportsStorageEncryption         |  True              ||
||  SupportsStorageThroughput         |  False             ||
||  Vpc                               |  True              ||
|+------------------------------------+--------------------+|
|||                   AvailabilityZones                   |||
||+-------------------------------------------------------+||
|||                         Name                          |||
||+-------------------------------------------------------+||
|||  us-west-2a                                           |||
|||  us-west-2b                                           |||
|||  us-west-2c                                           |||
||+-------------------------------------------------------+||
|||              AvailableProcessorFeatures               |||
||+-----------------+-----------------+-------------------+||
|||  AllowedValues  |  DefaultValue   |       Name        |||
||+-----------------+-----------------+-------------------+||
|||  1,2,3,4        |  4              |  coreCount        |||
|||  1              |  1              |  threadsPerCore   |||
||+-----------------+-----------------+-------------------+||

In addition, you can run the following commands for DB instance class processor information:

  • describe-db-instances – Shows the processor information for the specified DB instance

  • describe-db-snapshots – Shows the processor information for the specified DB snapshot

  • describe-valid-db-instance-modifications – Shows the valid modifications to the processor for the specified DB instance

In the output of the preceding command, the values for the processor features are null if Optimize CPU is not configured.

Example of setting the number of CPU cores for a DB instance

The following example modifies mydbinstance by setting the number of CPU cores to 4 threadsPerCore as 1. Apply the changes immediately by using --apply-immediately. If you want to apply the changes during the next scheduled maintenance window, omit --apply-immediately option.

aws rds modify-db-instance \
    --db-instance-identifier mydbinstance \
    --db-instance-class db.r7i.8xlarge \
    --processor-features "Name=coreCount,Value=4" "Name=threadsPerCore,Value=1" \
    --apply-immediately
Example of returning to default processor settings for a DB instance

The following example modifies mydbinstance by returning it to the default processor values for it.

aws rds modify-db-instance \
    --db-instance-identifier mydbinstance \
    --db-instance-class db.r7i.8xlarge \
    --use-default-processor-features \
    --apply-immediately