Managing Exadata Cloud Infrastructure I/O Resource Management (IORM)

This topic explains the I/O Resource Management (IORM) feature and how to enable it, modify the IORM settings, and disable it by using the Console or the API.

About IORM

The I/O Resource Management (IORM) feature allows you to manage how multiple databases share the I/O resources of an Oracle Exadata cloud VM cluster for systems using the new resource model or DB system

On an Exadata VM cluster or DB system, all databases share dedicated storage servers which include flash storage. By default, the databases are given equal priority with respect to these resources. The Exadata storage management software uses a first come, first served approach for query processing. If a database executes a major query that overloads I/O resources, overall system performance can be slowed down.

IORM allows you to assign priorities to your databases to ensure critical queries are processed first when workloads exceed their resource allocations. You assign priorities by creating directives that specify the number of shares for each database. The number of shares corresponds to a percentage of resources given to that database when I/O resources are stressed.

Directives work together with an overall optimization objective you set for managing the resources. The following objectives are available:

  • Auto - Recommended. IORM determines the optimization objective and continuously and dynamically determines the optimal settings, based on the workloads observed, and resource plans enabled.
  • Balanced - For critical OLTP and DSS workloads. This setting balances low disk latency and high throughput. This setting limits disk utilization of large I/Os to a lesser extent than low latency to achieve a balance between good latency and good throughput.
  • High throughput - For critical DSS workloads that require high throughput.
  • Low latency - For critical OLTP workloads. This setting provides the lowest possible latency by significantly limiting disk utilization.

Using the Console to Manage IORM

This topic only applies to Exadata Cloud Infrastructure systems using the new resource model.

Note

If you are enabling IORM for an Exadata DB system, see To enable IORM on your Exadata DB system.

Enabling IORM includes specifying an optimization objective and configuring your resource plan directives.

  1. Open the navigation menu. Click Oracle Database, then click Exadata at Oracle Cloud.
  2. Choose your Compartment.
  3. Click Exadata VM Clusters under the Exadata at Oracle Cloud.
  4. In the list of VM clusters, find the VM cluster for which you want to enable IORM, and click its highlighted name. The cluster's details are displayed, showing the IORM status as "Disabled."
  5. Click Enable IORM.

    It might take a minute for the Enable I/O Resource Management dialog to retrieve the VM cluster information.

  6. Select the objective to apply to the resource plan:

    • Auto - (Recommended) Dynamically changes the objective based on the resource plan and observed workloads.
    • Balanced - Weighs high throughput and low latency evenly.
    • High throughput - Provides the best throughput for DSS workloads.
    • Low latency - Provides the best latency for critical OLTP workloads.
  7. Configure the resource plan default directive by setting the number of shares. This number of shares is assigned to each database not associated with a specific directive.
  8. In the Resource Plan Directives section, add a directive for each database you want to assign a greater or lesser number of shares than the default directive.

    To add a directive, click + Additional Directive, then specify the database and the number of shares for that database.

  9. When you are done adding directives, click Enable.

    While the IORM configuration settings are being applied, the VM cluster details page shows the IORM status as "Updating." The update might take several minutes to complete but should have no impact on your ability to perform normal operations on your VM cluster. After a successful update, the IORM status shows as "Enabled."

To modify the IORM configuration on your cloud VM cluster

To enable IORM on your Exadata DB system

To modify the IORM configuration on your Exadata DB system

Use this procedure to change your IORM settings or to disable IORM.

Note

This topic only applies to Exadata Cloud Infrastructure instances using the DB system resource model.
  1. Open the navigation menu. Click Oracle Database, then click Bare Metal, VM, and Exadata.
  2. Choose your Compartment.
  3. In the list of DB systems, find the Exadata DB system for which you want to modify the IORM configuration, and click its highlighted name.

    The system details are displayed, showing the IORM status as "Enabled."

  4. Click Update IORM.
  5. In the Update I/O Resource Management dialog, take one of the following actions:

    • Change your settings - Specify a new objective and adjust your directives, as applicable, and then click Update.
    • Disable IORM - Click Disable IORM. Disabling IORM removes all your resource plan directives and restores a basic objective for I/O resource management.

    While the new IORM configuration settings are being applied, the system details page shows the IORM status as "Updating." The update might take several minutes to complete but should have no impact on your ability to perform normal operations on your DB system. After a successful update, the IORM status shows as "Enabled" or "Disabled," depending on the action you took.

Using the API to manage the I/O resources of an Exadata cloud VM cluster

For information about using the API and signing requests, see REST APIs and Security Credentials. For information about SDKs, see Software Development Kits and Command Line Interface.

Use these API operations to manage the I/O resources of an Exadata cloud VM cluster. (see The New Exadata Cloud Service Resource Model for more information on this resource type).

Use these API operations to manage the I/O resources of an Exadata DB system.