Rightsizing is the process of recommending the use of right instance type or right resources for an application to optimize cost for an organization. Typically, instances are overprovisioned for an application. Overprovisioning of resources results in resources, such as CPU, memory, and so on, being unused. In turn, underutilization leads to an increase in cost – you spend much more than what you should. 

If some instances are under-provisioned, the recommendation engine recommends upsizing of instances which might not result in cost savings, but improvement in application performance.

Recommendation Engine

The recommendation engine uses an algorithm based on CPU and memory and recommends the right set of actions (downsizing of instances) that results in significant cost reduction without affecting the application performance. This algorithm uses the default thresholds (for CPU and memory) to arrive at downsize or upsize recommendations.

The recommendation engine works as follows:

  • The algorithm matches the attributes ( CPU, memory, network, and storage capabilities) of running a virtual machine and compares the attributes with operational metrics, such as CPU utilization to arrive at the rightsize for instance.

  • The algorithm is cost-conscious and offers multiple candidate choices to resize the instance.

  • The threshold limitations can be set or modified in the Settings submenu of the Admin menu.

  • The Resize action is handled by the Workload Manager.

  • When suggesting resizing recommendations, an instance with RI opportunities is preferred for instances of the same type. This ensures maximum utilization of resources and minimum cost.

Proportional Resizing

The recommendation engine recommends instances based on the CPU or memory utilization of the instance over a period of time. Based on the factors of underutilization or overutilization, appropriate instances are identified to ensure CPU or memory ratios will be maintained approximately. If Proportional Resizing, in the Settings submenu of the Admin menu, is turned off, equal memory instances with appropriate CPU counts will be recommended.

Clouds That Support Rightsizing and Nuances

The following table describes the clouds, its resources that are supported for rightsizing and the nuances, applicable for each cloud:

CloudSupported ResourcesNuances


Managed and unmanaged VMs



Managed and unmanaged VMs



Managed and unmanaged VMs

Cisco does not recommend custom instance sizes for Google Cloud Platform (GCP). Predefined instance types are only supported for rightsizing recommendation.

VMware vCenter

Managed and unmanaged VMs

The recommendations appear when prices for the cloud instance types are specified in the Instance Types Settings page. The prices are specified by a Cost Optimizer admin.

The average values of CPU and memory metrics are used for rightsizing recommendations.

Rightsizing Report

The Rightsizing report is divided into the following:

  • Instance Utilization

  • Recommendations

Instance Utilization

This report provides information about all running instances against the resize threshold limits, which is displayed in braces, as defined in the Settings submenu of the Admin menu.

  • Ideal Utilization – Instances running between the maximum and minimum threshold limits and for which no action is required.

  • Unused – Instances not being used, which can be stopped or terminated. 

  • Underutilized – Instances running below the minimum threshold limit and must be downsized.

  • Overutilized – Instances running above the maximum threshold limit and must be upsized.


The Recommendations report provides detailed recommendations for all running – managed and unmanaged VMs – under the following tabs: 

  • Underutilized

  • Unused 

  • Overutilized

Accounts must be enabled with PROVISIONING_REPORTING for the rightsizing engine to offer rightsizing recommendations. Support for recommendations in accounts with other roles will be added in a future release.

The following table explains the columns in the Recommendations report.

Column HeadingDescription


Total number of VMs on which rightsizing recommendations can be applied.

Maximum Potential Savings

Maximum savings incurred by applying the rightsizing recommendations on each VM.

Show Dismissed

Displays dismissed VMs in the recommendations report.


Displays the VM name as a link. Click the link to view details about the VM.

Current Size

Current instance model type on which the VM is running.

Low/High Utilization

Actual utilization numbers (in percent) for the instances observed for a specific time.

Resize Recommendation

Instance model type to which the VM can be resized from the current size and the potential savings that can be achieved by choosing the specified instance.

Potential Savings

Savings, based on current utilization, incurred as a result of choosing the recommended VM.


Allows you to do the following:

  • Resize – Resizes to the recommended instance.
  • Dismiss – Remove the instance from the recommendation report. To include the dismissed instances in the report, toggle ON the Show Dismissed icon.
  • Stop – Stops the instance temporarily to restart it at a later time.
  • Terminate – Shuts down the instance.

While Resize is available in Underutilized and Overutilized recommendations report, Stop and Terminate are available in Unused recommendations report.

The Actions button above the table allows you to stop and terminate all or selected VMs listed on the page.

Underutilized Tab

The following is a sample screenshot of the Underutilized tab in the Recommendations report. A VM is considered underutilized if the value in the High Utilization field is consistently lower (for a specific time) than the value mentioned in Min. CPU Threshold field in the Settings submenu of the Admin menu.

Unused Tab

An instance is termed as an unused instance if the utilization is below the terminate threshold as specified in the Rightsizing card of the Settings submenu when the Rightsize Analyzer collects the data. If the utilization is above the terminate threshold settings as specified in the Rightsizing card when the rightsize analyzer (see Data Collection) runs the next day, the instance ceases to be an unused instance. 

The following is a sample screenshot of the Unused tab in the Recommendations report.

Use the Actions button to stop or terminate all or selected VMs listed on the page.

Overutilized Tab

The following is a sample screenshot of the Overutilized tab in the Recommendations report. A VM is considered overutilized if the value in the High Utilization field is consistently higher (for a specific time) than the value mentioned in the Max. CPU Threshold field in the Settings submenu of the Admin menu

If the Show Cost-incurring Upsize Recommendations option in the Settings submenu is turned on, upsize recommendations for overutilized instances are provided though the recommendations do not result in potential savings.

Advanced Options

You can do the following on the Rightsizing report:

  • Download the report

  • Save filters in the report

  • Schedule a report

Saving Filters

You can choose to save a combination of options in the Filter menu for future use through the Save Filters feature so that you can quickly access and use the filter at a later time. To save a filter, do the following: 

  1. Choose the required filter options in the Filter Panel pane.

  2. The Save button appears. The Save New Filter dialog appears. At this point, you can remove the selected filters by choosing the Reset button.

  3. Specify a name for this filter and click Save. A status message appears indicating that the filter has been saved.

  4. You can access and view the saved filters from the dropdown list.

You can mark the filter as a favorite by clicking the pin icon next to the filter name.

Scheduling Reports

The Scheduler icon allows you to schedule report generation periodically on a fixed date or at intervals. To create a schedule, do the following:

  1. Click the Scheduler icon. The Schedule dialog appears.

  2. Click Schedule New

  3. Do the following:

    1. Enter a name for the schedule.

    2. Choose filtering options for the schedule from the Filtered By field. The information in this field is populated when you save the filtering options in the page. You can choose to select a filter or leave the field empty.

    3. Choose the date range.

    4. Select the recipients the report must be sent to.

    5. Specify the start date.

    6. Toggle on the Recurrence button to send the report at intervals.

    7. In the Repeats Every area, specify the number of times the report must be sent to the recipients and choose the interval – Daily or Weekly. if you choose Weekly, you can also specify the days of the week when the report is sent.

    8. Select the period to end the schedule. The options are:

      1. Never – Send report forever or until the schedule is deleted.

      2. On – Date when the report should be sent.

      3. After – Number of occurrences after which the report is not scheduled.

  4. Click Save. The report is displayed in the Scheduled Report Name dialog as shown in the sample screenshot below.

    Optionally, you can use the Edit and Delete options in the Actions column to make changes to the schedule or delete the report respectively.

  5. Click Done to close the dialog.

Options in the Actions Column

As mentioned in the table above, the Action button performs the following:

  • Dismiss

  • Resize

  • Stop

  • Terminate

Choose Dismiss to remove the recommendations for a VM from the report.


The Resize button resizes a VM to the recommended instance type. If a VM in the recommendations table is an unmanaged VM, the VM must be imported first before it is resized. To resize a VM, perform the following steps:

  1. Click the Resize button. The Resize VM Name dialog appears.

  2. Click Yes. A dialog appears displaying the current size of the VM, the recommended size of the VM, and the potential savings as a result of resizing the instance.

  3. Click Resize. A spinning circle icon appears in the Actions column indicating that resize is in progress.

  4. On completion, a notification appears displaying that the VM has been resized.

Navigate to the History tab in VM Details page in Workload Manager (see Virtual Machine Management > VM Details) for a complete history of actions performed on this VM.

Stopping and Terminating a VM

You can stop and terminate a VM through the following methods:

  • Use the Actions Button to stop or terminate all or selected VMs by either choosing the checkbox against each VM or choosing the checkbox in the report header.

  • Hover over the Actions column against a VM to individually stop or terminate VMs. 

When you stop a VM, the VM is shut down and you will not be charged for the usage until you plan to start it again in the near future. When you terminate a VM, the VM is shut down and permanently removed. You are not charged for the usage any longer. Therefore, you should stop a VM if you plan to start it again else, you may terminate the VM instead of stopping it to save cost.

If a VM in the recommendations table is an unmanaged VM, the VM must be imported first before it is stopped or terminated.

To stop or terminate all VMs in the Unused tab, click the Actions button, and choose the Stop All or Terminate All options. Irrespective of the pages the report spans, all listed VMs are stopped or terminated.

To stop or terminate a VM, perform the following steps:

  1. Do one of the following:

    1. For multiple VMs, select the VMs by clicking the checkbox adjacent to a VM and click the Actions button. 

    2. For individual VMs, hover on the Actions column. Click the icon to display the options – Stop or Terminate and choose the appropriate option. 
      The Stop VM Name dialog appears.

  2. Click Yes. A spinning circle icon appears in the Actions column indicating that chosen action is in progress.
  3. On completion, a notification appears displaying that the VM has been stopped or terminated.

  • No labels
Terms & Conditions Privacy Statement Cookies Trademarks