Forecasting

Overview

Disk Forecasting uses advanced predictive analytics and machine learning technology to show you when you'll run out of storage space and predict how much space you'll need going forward. 

There are two Disk Forecasting methods available:

  • Standard
    • Standard forecasts use an enhanced linear regression algorithm. It's able to analyze your disk’s usage history, identify manual interventions such as someone truncating or deleting a large file to free space, and ensures those events don’t skew your forecast.
  • Advanced
    • Advanced forecasts learn from the workload on your storage volumes and use R Services (In-Database) on the SQL Server hosting the SentryOne database.

For more information about storage forecasting in SentryOne, please see the follow blog posts:

Getting Started

Follow these steps to configure your SQL Server (hosting the SentryOne database) and SentryOne client to use storage forecasting:

  1. Verify SQL Server requirements and configure environment as needed
  2. Configure SentryOne monitoring service settings

Once your environment has been configured, you'll need to wait at least 24 hours to have disk forecasting data available. Then you'll be able to use the following features with disk forecasting:

  • Disk Space Analysis view
  • Advisory conditions for disk forecasting
  • The Windows Disk Forecasting report

Step 1. Requirements & Configuration

Disk Forecasting ModeAdditional Requirements
StandardThere are no additional requirements for Standard Disk Forecasting. You can proceed to Step 2 to configure the monitoring service settings.
AdvancedThe Advanced Disk Forecasting feature requires:

  1. A SentryOne database on SQL Server 2016 or later with R/ML Services in-Database enabled. 
  2. You must turn on the external scripts enabled option in SQL Server for the instance hosting the SentryOne database. 
  3. The SQL Server Launchpad service must also be running before using Advanced Disk Forecasting. 
Note:  If any of the above features or settings were not in place, you should restart the SentryOne client after setting them, then select the Advanced Disk Forecasting mode in Monitoring Service Settings as described in the Settings section of this article.

SQL Server Feature:  R/ML Services

How do I know if the Advanced Analytics Extensions feature is installed?

If you're unsure about the installation status of the R/ML Services in-Database feature for your existing SQL Server installation, you'll know for certain when you attempt to turn on the external scripts enabled option and the following error appears:

Msg 39020, Level 16, State 1, Procedure sp_configure, Line 166 [Batch Start Line 0] Feature 'Advanced Analytics Extensions' is not installed. Please consult Books Online for more information on this feature.

How do I install R/ML Services in Database (Advanced Analytics Extensions)?

Follow the instructions provided from the Install SQL Server 2016 R Services article on Microsoft Docs to add this feature to your existing SQL Server installation.

SQL Server Configuration:  External Scripts Enabled

How do I verify that external scripts enabled is turned on in SQL Server?

Check external scripts enabled by running:

EXECUTE sp_configure  'external scripts enabled'

In this example, the run_value is set to 0, meaning that external scripts enabled is false/turned off. If your run_value is set to 1, then this feature is already enabled.

Note:  The config_value displays what the run_value will be the next time that SQL Server restarts. If it is set to 0, then the feature will be disabled after a restart.

How do enable external scripts enabled in SQL Server?

Execute the following to turn on external scripts enabled and reconfigure the SQL Server option:

sp_configure 'external scripts enabled', 1;
RECONFIGURE WITH OVERRIDE; 

This is the success message:

Configuration option 'external scripts enabled' changed from 0 to 1. Run the RECONFIGURE statement to install.

At this point, the config_value is changed, but a restart is required to set the run_value.

Do I need to restart SQL Server to complete the process?

Yes, restart the SQL Server Instance to complete setting the run_value

Additional Information: If needed, follow the instructions from Microsoft Docs to restart the database engine.

 Verify that the config_value and run_value are both set to 1. Check external scripts enabled by running:

EXECUTE sp_configure  'external scripts enabled'

How do I verify that SQL Server Launchpad is running?

Open the Services window to verify that MSSQLLaunchpad / SQL Server Launchpad (MSSQLSERVER) is running:

Additional Information: If needed, see the Microsoft article for more details on verifying and testing a successful installation.

Step 2. Monitoring Service Settings

You have the option to select either Advanced or Standard mode.

Adding a Forecast Schedule

  1. Select Global Settings in the Navigator pane, and then select Forecasts.
    SentryOne Select Forecasts
  2. Select either Standard or Advanced from the drop-down menu.  
    SentryOne Select Standard or Advanced
  3. Select the ellipses icon, then select New to add a new Forecast Schedule.  
    SentryOne Select New
  4. Select the desired parameters from the Schedule Properties window, then select OK.
  5. Select the number of days desired for the Days Forward to Forecast. The default is 180 days.
    SentryOne Days Forward to Forecast
  6. Select the Save iconSentryOne Save Iconto save the Disk Forecast.

Editing or Deleting a Forecast Schedule 

To edit a Forecast Schedule, select the ellipses icon, then select Edit to change the Schedule Properties parameters.
SentryOne Select Edit

Select OK to save the changes, select the Save iconSentryOne Save Icon, then select Regenerate Global Forecasts to refresh the Disk Forecast. 

SentryOne Select Ok

SentryOne Select Regenerate

To delete a Forecast Schedule, select the ellipses icon, choose the desired Forecast Schedule from the list, and then select Delete.

SentryOne Select Delete

The following message appears; either select Yes to remove the Forecast Schedule from the list, or select No to keep the Forecast Schedule in the list. Select OK in the Select a Schedule window to save your changes.

SentryOne Delete Message

Note:  A Disk Forecast runs automatically each day even if there is no schedule selected. A Forecast Schedule is applied to better control when the forecast runs.

Disk Space Analysis View

Note:  Disk space data is not generated until 24 hours after a Disk Forecast runs.

Select your desired target from the Navigator pane, and then select the Disk Space tab. Select the desired Logical Drive, and the Disk Forecasting chart appears at the bottom of the screen. On the Disk Space chart a tool tip displays with the Free Space and Forecasted Exhaustion Date. 

Note:  The cell under Forecasted Exhaustion will be highlighted orange if the Forecasted Exhaustion date is within 180 days, and it will be red if it is within 90 days.

The Free Space chart displays the following parameters:

Free Space Chart ParametersDescription
Disk Free SpaceAmount of available (free) hard drive space on a given disk.
Prediction IntervalAn estimated interval that represents the range of values that a future observation will lie within at a specific point in time based on the provided probability. The forecast is generated using a 70% prediction interval, so there is a 70% probability that the actual free disk space on a given date will fall within the forecasted prediction interval.  
Forecasted Free SpaceEstimated amount of Disk Free Space that will be available for a given disk and date.

Note:   

  • The forecast displayed is out 180 days, but it can be scheduled for up to 3 years.
  • The length of the Disk Forecasting will impact the storage and accuracy of the data.

Advisory Conditions

There are advisory conditions available to work with storage forecasting:

Reports

See the Windows Disk Forecast report available under Reports > Performance Analysis > Disk/File Space:

For more information about this report, see the Reports Menus article.