Scaling an Exadata Cloud at Customer Instance

Modifying the Compute Node Processing Power

If an Exadata Cloud at Customer instance requires more compute node processing power, you can scale up the number of enabled CPU cores in the current Exadata system configuration. A capability known as bursting enables you to modify the compute node processing power temporarily, or you can add compute node processing power on a more permanent basis.

The maximum number of enabled CPU cores depends on your system configuration. See Exadata System Configuration. However, your subscription may impose extra limits.

You can also choose to enable the CPU oversubscription feature.

To modify the number of enabled CPU cores or enable the CPU oversubscription feature in an existing Exadata Cloud at Customer instance:

Open the My Services dashboard.

For detailed instructions, see Accessing the My Services Dashboard and the Oracle Database Cloud Service Console.
Click the action menu () in the tile that is associated with Exadata Cloud at Customer and choose View Details.

The Service Details page is displayed, with the Overview tab showing.
Locate your service instance in the list. Click the action menu () located beside the service instance name and choose Modify.

The Modify Oracle Database Exadata Cloud Service Instance wizard starts and the Instance Details page is displayed.
If it is displayed on the Instance Details page, select the OCPUs option to indicate that you want to modify the number of enabled CPU cores within an existing Exadata Cloud at Customer instance.
On the Instance Details page, specify the type of scaling operation that you want to perform and use the slider control to set the number of enabled CPU cores on each compute node. You can also choose to enable CPU oversubscription. Then, click Modify.
1. If it is not already enabled, you can choose to enable CPU oversubscription on the Exadata Cloud at Customer instance by selecting the CPU Oversubscription option. See CPU Oversubscription.
  
  Note:
  After it is enabled, you cannot disable CPU oversubscription.
2. Specify the type of scaling operation that you want to perform by selecting the Subscription option or the Burst option:
  - Select Subscription if you want to scale the service in line with a subscription change.
    
    To use this option, you must first adjust your subscription and purchase the additional CPU core entitlements. Thereafter, the slider control enables the placement of the additional CPU cores on your compute nodes.
  - Select Burst if you want to temporarily scale the service instance.
    
    With bursting, you can quickly scale up beyond your subscription level to cater for workload peaks. You can also scale back to the subscription level at any time.
    
    CPU cores beyond your subscription level are charged separately using an hourly rate for the bursting period. These charges begin immediately after you enable the CPU cores in your service instance, and continue until you scale back to the subscription level.
    
    Note:
    For non-metered subscriptions only, the maximum number of enabled CPU cores available with bursting is limited to twice the number of CPU cores in the associated service subscription. For example, if your service subscription contains 11 enabled CPU cores on each compute node, then the bursting maximum is 22 CPU cores on each compute node. This limit does not apply to other subscription types, such as Universal Credits.
3. Use the slider control to set the new number of enabled CPU cores on each compute node. When you make a change, the change is reflected in the Configuration after Update summary. At any point, you can click Reset to return the slider to its original setting.
  
  Note:
  The slider setting represents the total number of enabled CPU cores for each compute node and not the number of additional CPU cores to enable.
On the Confirmation page, review the configuration settings. If you are satisfied, click Modify.

Otherwise, click Cancel on the Confirmation page and again on the Instance Details page to cancel the wizard without updating the service instance.

Modifying the number of enabled CPU cores and enabling CPU oversubscription are online operations. Compute nodes are not rebooted because of these operations.

If the Exadata Cloud at Customer instance is not enabled to support multiple virtual machine (VM) clusters, then changes to the number of enabled CPU cores are automatically reflected in each compute node user domain (DomU). However, if the instance is enabled to support multiple VM clusters, then changes to the number of enabled CPU cores in the an Exadata Cloud at Customer instance are not automatically applied to the underlying VM clusters. In this case, you must also modify the VM clusters separately to utilize the enabled CPU resources in the an Exadata Cloud at Customer instance. See Modifying an Existing VM Cluster.

The Oracle Database instance caging feature is enabled by explicitly setting the CPU_COUNT database initialization parameter. That setting is not affected by modifying the number of enabled CPU cores. Therefore, if you are using the instance caging feature you must explicitly alter the CPU_COUNT setting to match any changes to the service instance. If CPU_COUNT is set to 0 (its default setting), then instance caging is disabled and Oracle Database continuously monitors the number of CPUs reported by the operating system and uses the current count.

Adding Exadata Storage

You can increase the Exadata storage in your current Exadata system configuration by adding Exadata Storage Servers subject to the following conditions:

Each Exadata Cloud at Customer system configuration can have an absolute maximum of 12 Exadata Storage Servers.
The Exadata Cloud at Customer system configuration must be based on Oracle Exadata X7 hardware or Oracle Exadata X6 hardware.
The Exadata Cloud at Customer service instance must be enabled to support multiple virtual machine (VM) clusters.

To add Exadata Storage Servers to your current Exadata system configuration, you must first procure subscriptions for the additional storage servers. Then, an Oracle field engineer physically installs the Exadata Storage Server hardware and registers it in the system.

After the Exadata Storage Server hardware is physically provisioned and registered, you can use the following procedure to add the Exadata storage to your Exadata Cloud at Customer instance:

Open the My Services dashboard.

For detailed instructions, see Accessing the My Services Dashboard and the Oracle Database Cloud Service Console.
Click the action menu () in the tile that is associated with Exadata Cloud at Customer and choose View Details.

The Service Details page is displayed, with the Overview tab showing.
Locate your service instance in the list. Click the action menu () located beside the service instance name and choose Modify.

The Modify Oracle Database Exadata Cloud Service Instance wizard starts and the Instance Details page is displayed.
On the Instance Details page, select the Storage option to indicate that you want to add Exadata storage to the Exadata Cloud at Customer instance.
Confirm that the Instance Details page shows the correct number of Exadata Storage Servers to be added. Then, click Modify.
On the Confirmation page, review the configuration settings. If you are satisfied, click Modify.

Otherwise, click Cancel on the Confirmation page and again on the Instance Details page to cancel the wizard without updating the service instance.

Ensure that the addition of the Exadata Storage Servers completes successfully before you attempt to add anymore Exadata Storage Servers or compute nodes. If the operation fails for any reason, the failure must be remedied before any attempt to add anymore Exadata Storage Servers or compute nodes. Otherwise, the system may be left in an inconsistent state requiring manual intervention by Oracle.

Adding Exadata storage to the Exadata system configuration is an online operation, which does not affect the availability of your database deployments.

Adding Exadata Storage Servers triggers a rebalance operation, which occurs in the background and is designed to have minimal impact on the I/O performance of your system. Specifically, the existing storage allocation for each VM cluster is rebalanced across all of the Exadata Storage Servers, including the new ones. And, the newly added storage is proportionally distributed to the VM clusters, increasing the allocated storage for each VM cluster.

If you want to further modify the amount of storage that is allocated to a VM cluster, you must do it separately for each VM cluster. See Modifying an Existing VM Cluster.

Adding Compute Nodes

You can increase compute resources in your current Exadata system configuration by adding Exadata compute nodes subject to the following conditions:

Each Exadata Cloud at Customer system configuration can have an absolute maximum of eight compute nodes. However, the practical maximum is more limited if you don't have enough free IP addresses for the additional compute nodes.

Specifically, if your system is configured so that each VM cluster client network subnet is defined using a /28 CIDR block (N.N.N.N/28) and each VM cluster backup network subnet is defined using a /29 CIDR block, then your immediate expansion potential is limited to five compute servers. In such cases, expansion to more than five compute servers requires the redeployment of Exadata Cloud at Customer, which includes deleting and re-creating all of the VM clusters and database deployments on the system.
The Exadata Cloud at Customer system configuration must be based on Oracle Exadata X7 hardware. You cannot add compute nodes to a starter system configuration based on Oracle Exadata X6 hardware.
The Exadata Cloud at Customer service instance must be enabled to support multiple virtual machine (VM) clusters.

To add compute nodes to your current Exadata system configuration, you must first procure subscriptions for the additional compute nodes. Then, an Oracle field engineer physically installs the compute node hardware and registers it in the system.

For non-metered subscriptions only, before you use the following procedure to add the compute nodes to your Exadata Cloud at Customer instance, you must disable (scale back to zero) CPU core bursting. See Modifying the Compute Node Processing Power.

After the compute node hardware is physically provisioned and registered, you can use the following procedure to add the compute nodes to your Exadata Cloud at Customer instance:

Open the My Services dashboard.

For detailed instructions, see Accessing the My Services Dashboard and the Oracle Database Cloud Service Console.
Click the action menu () in the tile that is associated with Exadata Cloud at Customer and choose View Details.

The Service Details page is displayed, with the Overview tab showing.
Locate your service instance in the list. Click the action menu () located beside the service instance name and choose Modify.

The Modify Oracle Database Exadata Cloud Service Instance wizard starts and the Instance Details page is displayed.
On the Instance Details page, select the Compute Nodes option to indicate that you want to add compute nodes to the Exadata Cloud at Customer instance.
Confirm that the Instance Details page shows the correct number of compute nodes to be added. Then, click Modify.
On the Confirmation page, review the configuration settings. If you are satisfied, click Modify.

Otherwise, click Cancel on the Confirmation page and again on the Instance Details page to cancel the wizard without updating the service instance.

Ensure that the addition of the compute nodes completes successfully before you attempt to add anymore compute nodes or Exadata Storage Servers. If the operation fails for any reason, the failure must be remedied before any attempt to add anymore compute nodes or Exadata Storage Servers. Otherwise, the system may be left in an inconsistent state requiring manual intervention by Oracle.

Adding compute nodes to your Exadata Cloud at Customer instance is an online operation, which does not affect the availability of your existing VM clusters and database deployments.

After the compute nodes are added to your Exadata Cloud at Customer instance, you can use the new compute nodes when you create a VM cluster. You can also add the new compute nodes to an existing VM cluster. See Creating a VM Cluster and Modifying an Existing VM Cluster.