Get prediction results for Standby pools (Preview)

Important

Prediction results for standby pools is currently in preview. Previews are made available to you on the condition that you agree to the supplemental terms of use. Some aspects of this feature may change prior to general availability (GA).

To effectively manage and optimize your standby pool for Virtual Machine Scale Sets, you can use the Standby Pool runtime view APIs to retrieve prediction results. These results are available 2-3 weeks after creating the standby pool and provide insights into the predicted number of instances that will be requested from the pool for each hour over a 12-hour period. The predictions include the accuracy of the forecast and a historical view of instances requested from the pool over the past 12 hours, helping you make informed decisions to right-size your standby pool and improve operational efficiency.

While the prediction results provide valuable insights, they are not a guarantee and should be treated as a suggested size for your pool. The actual number of instances requested from the pool may vary depending on the specific demands of your workload. Additionally, the longer the prediction engine is able to monitor and analyze your workload trends, the more accurate and reliable the prediction results will become over time.

Prediction information

Note

Prediction values will not show unless the standby pool has been provisioned for 2-3 weeks.

The prediction results provide detailed insights into the expected behavior of your standby pool. These results include metadata about the forecast, such as accuracy, time intervals, and historical data, as well as the predicted number of instances requested during the forecast period. Use this information to analyze trends, optimize your standby pool size, and improve operational efficiency. Below is a description of the key values included in the prediction results:

Value	Description
forecastInfo	A JSON string containing additional metadata about the forecast, such as accuracy, time intervals, and recent history of requested instances.
SeriesUnitIntervalInMins	The time interval, in minutes, between each data point in the forecast. For example, a value of 60 indicates hourly intervals.
InstancesRequestedCountRecentHistory	An array of historical data showing the number of instances requested from the standby pool over the past 12 hours.
ForecastAccuracy	The accuracy of the forecast as a percentage. A higher value indicates a more reliable prediction.
forecastStartTime	The timestamp indicating when the forecast period begins.
instancesRequestedCount	An array of predicted instance counts for each time interval in the forecast period.

CLI

az standby-vm-pool status --resource-group myResourceGroup --name myStandbyPool

{
  "id": "/subscriptions/{subscriptionId}/resourceGroups/myResourceGroup/providers/Microsoft.StandbyPool/standbyVirtualMachinePools/myStandbyPool/runtimeViews/latest",
    {
      "instanceCountsByState": [
        {
          "count": 0,
          "state": "Creating"
        },
        {
          "count": 0,
          "state": "Starting"
        },
        {
          "count": 1,
          "state": "Running"
        },
        {
          "count": 3,
          "state": "Deallocating"
        },
        {
          "count": 7,
          "state": "Deallocated"
        },
         {
            "state": "Hibernating",
            "count": 0
        },
        {
            "state": "Hibernated",
            "count": 0
        },
        {
          "count": 0,
          "state": "Deleting"
        }
      ]
   }
  "name": "latest",
  "prediction": {
    "forecastInfo": "{\"SeriesUnitIntervalInMins\":60,\"InstancesRequestedCountRecentHistory\":[10,11,9,11,12,11,10,9,7,11,10,12],\"ForecastAccuracy\":90.0}",
    "forecastStartTime": "2025-05-09T17:00:00-07:00",
    "forecastValues": {
       "instancesRequestedCount": [ 10,10,11,12,9,11,11,12,13,10,10,8]}},
  "provisioningState": "Succeeded",
  "resourceGroup": "myResourceGroup",
  "status": {
    "code": "HealthState/healthy"
  },
  "type": "Microsoft.StandbyPool/standbyVirtualMachinePools/runtimeViews"
}

PowerShell

Get-AzStandbyVMPoolStatus -ResourceGroupName myResourceGroup -Name myStandbyPool

Id: /subscriptions/{subscriptionId}/resourceGroups/myResourceGroup/providers/Microsoft.StandbyPool/standbyVirtualMachinePools/mmyStandbyPool/runtimeViews/latest
InstanceCountSummary: {
        "instanceCountsByState": [
        {
            "state": "Creating",
            "count": 0
        },
        {
            "state": "Starting",
            "count": 0
        },
        {
            "state": "Running",
            "count": 1
        },
        {
            "state": "Deallocating",
            "count": 3
        },
        {
            "state": "Deallocated",
            "count": 7
        },
         {
            "state": "Hibernating",
            "count": 0
        },
        {
            "state": "Hibernated",
            "count": 0
        },
        {
            "state": "Deleting",
            "count": 0
        }
       ]
     }
Name                                 : latest
PredictionForecastInfo               : {"SeriesUnitIntervalInMins":60,"InstancesRequestedCountRecentHistory":[10,11,10,11,12,8,9,11,10,12,7,11],"ForecastAccuracy":85.0}
forecastValues                       : { "instancesRequestedCount": [10,11,11,10,12,13,11,10,9,10,11,12]}
PredictionForecastStartTime          : 5/10/2025 12:00:00 AM
ProvisioningState                    : Succeeded
ResourceGroupName                    : myResourceGroup
StatusCode                           : HealthState/healthy
Type                                 : Microsoft.StandbyPool/standbyVirtualMachinePools/runtimeViews

REST

GET https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.StandbyPool/standbyVirtualMachinePools/{standbyVirtualMachinePoolName}/runtimeViews/latest?api-version=2025-03-01

{
  "properties": {
        "instanceCountSummary": [
      {
        "instanceCountsByState": [
          {
            "state": "Creating",
            "count": 0
          },
          {
            "state": "Starting",
            "count": 0
          },
          {
            "state": "Running",
            "count": 2
          },
          {
            "state": "Deallocating",
            "count": 3
          },
          {
            "state": "Deallocated",
            "count": 15
          },
          {
            "state": "Hibernating",
            "count": 0
          },
          {
            "state": "Hibernated",
            "count": 0
          },
          {
            "state": "Deleting",
            "count": 0
          }
        ]
      }
    ],
    "provisioningState": "Succeeded",
    "status": {
      "code": "HealthState/healthy",
      "message": "The pool is healthy."
    },
    "prediction": {
      "forecastValues": {
        "instancesRequestedCount": [24,10,20,12,15,10,15,23,14,16,17,19]
      },
      "forecastStartTime": "2025-02-14T01:34:59.228Z",
      "forecastInfo": "{\"forecastAccuracy\": 85, \"seriesUnitIntervalInMins\": 60, \"instancesRequestedCount_recentHistory\": \"[9,4,2,8,8,2,3,6,5,3,2,6]\"}"
    }
  },
  "id": "/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.StandbyPool/standbyVirtualMachinePools/{standbyPoolName}/runtimeViews/latest",
  "name": "pool",
  "type": "Microsoft.StandbyPool/standbyVirtualMachinePools/runtimeViews",
  "systemData": {
    "createdBy": "pooluser@microsoft.com",
    "createdByType": "User",
    "createdAt": "2025-02-14T23:31:59.679Z",
    "lastModifiedBy": "pooluser@microsoft.com",
    "lastModifiedByType": "User",
    "lastModifiedAt": "2025-02-14T23:31:59.679Z"
  }
}

Next steps

Review the most frequently asked questions about standby pools for Virtual Machine Scale Sets.