Performance Forecast for Datastores
This report forecasts free and provisioned space, latency and IOPs resource utilization for datastores.
The Performance Forecast for Datastores report forecasts how many days remain before the level of resource utilization reaches the specified threshold values. The report allows analyzing the following datastore resource utilization parameters: free space, provisioned space, read and write latency, disk IOPs.
To calculate future datastore performance, the report analyzes historical performance data for the specified period in the past, calculates the performance utilization trend and applies this trend to the forecast horizon. For better forecast accuracy, along with the performance trend the report provides trend’s confidence interval that represent the best- and worst-case scenarios. This allows you to estimate various possible outcomes and helps you rationally plan your resources.
If one or more specified thresholds are breached within the forecast interval, the report marks the datastore as problematic and lists constraining resources for it. The report also provides recommendations on appropriate resource allocation to prevent possible resource shortfalls in future.
Performance Data From: defines a date in the past starting from which historical performance data will be used to calculate the performance trend. The report analyzes historical performance data starting from this date to the current date (data collection period).
To make a forecast, the report must use historical performance data for at least 72 hours.
Forecast Horizon: defines the forecast period. The calculated performance utilization trend is applied to the time interval that starts from the current date to the forecast horizon date.
The date in the Forecast Horizon field must be a date in future.
Show details: defines whether the report will display expanded or collapsed charts.
Mode: defines whether the report will display all results or problematic areas only (problematic areas are datastores for which resource utilization thresholds will be breached within the forecast period).
Scope: defines a list of Groups or Objects that will be analyzed in the report (by default, the VMware Datastores group is selected). The Add Group option returns a Group and all objects that a group contains. The Add Object option returns only the selected object.
Threshold: Datastore Free Space (%): defines the free space threshold as a percentage of total available datastore space.
Threshold: Datastore Provisioned Space (%): defines the provisioned space threshold as a percentage of total available datastore space.
Threshold: Datastore Max Device Read Latency (ms): defines the maximum read latency threshold in millisecond.
Threshold: Datastore Max Device Write Latency (ms): defines the maximum write latency threshold in millisecond.
Threshold: Datastore IOPS: defines datastore IOPS threshold.
Aspects to be Analyzed: defines what types of metrics will be analyzed in the report (Free Space, Provisioned Space, Max Device Read Latency, Max Device Write Latency or IOPS).
If you choose not to analyze an aspect, the report will ignore the threshold specified for this aspect.
Forecast the number of days left before the amount of free space on the selected datastores reaches 30%, provisioned space reaches 150%, max read and write latency reach 70 and 85ms correspondingly, and datastore IOPS reach 900. Make sure that these thresholds will not be breached within the next 30 days. Use the historical performance data for the previous month to calculate the resource utilization trend.
- Open the Performance Forecast for Datastores report.
- From the Performance Data From list, select Previous Month > First Day.
- From the Forecast Horizon list, select a date in future (30 days from today).
- From the Show details list, select Expand Charts.
- From the Mode list, select Show problematic areas only.
- In the Scope section, select VMware Datastores and click Remove. Then search for available datastores to include in the report.
Click Add Object. In the Add Object window, click Options. In the Options window, click Add. In the Class Name search box, enter datastore and click Search. Select the VMware Datastore class in the list of search results, click Add and click OK. In the Options windows, click OK to apply the filter. In the Add Object window, click Search. The search will return a list of objects that belong to the VMware Datastore class. Select the necessary datastores in the list, click Add and click OK.
- In the Threshold: Datastore Free Space (%) field, enter 30.
- In the Threshold: Datastore Provisioned Space (%) field, enter 150.
- In the Threshold: Datastore Max Device Read Latency (ms) field, enter 70.
- In the Threshold: Datastore Max Device Write Latency (ms) field, enter 85.
- In the Threshold: Datastore IOPS field, enter 900.
- In the Aspects to be Analyzed field, select all aspects.
- Click Run to view the report.
The Virtual Infrastructure Described table will provide an overview for all datastores included in the report scope: total capacity, amount of free and provisioned space, amount of space consumed by unknown files and the number of VMs residing on the datastores.
The Performance Forecast Analysis and Recommendations table will provide the following details for every datastore:
Name of the datastore.
Result of the prediction analysis. Possible analysis results are:
Resource for which the specified threshold will be breached first within the forecast period.
For example, both Datastore Free Space (%) and Datastore Provisioned Space (%) thresholds will be breached within the forecast period and the Datastore Free Space (%) is reported to be breached first. In this case, the report will display Free Space as the constraining resource. However, the Recommendations will be provided both for Free and Provisioned Space resources.
Number of days left before the constraining resource threshold is breached. The number of days is shown as the worst-to-best case range.
Recommendations on appropriate resource allocation.
Recommendations for a resource will be provided in case the specified threshold for the resource is breached within the forecast period or has already been breached within the data collection period.
*Provided results and recommendations are based on the worst-case scenario.
The Overall Recommendations table will provide recommendations for all datastores included in the report scope.
Report details will provide in-depth forecast information for every datastore included in the report scope.
The Virtual Infrastructure Described table will provide an overview for the datastore: total capacity, amount of free and provisioned space, amount of space consumed by unknown files and the number of VMs residing on the datastore.
The Performance Forecast section will show a chart and a details table for each analyzed datastore resource.
The performance forecast charts will display the following types of data series for the analyzed data collection period:
- Trend and its deviation represent resource utilization trend and the 95% confidence interval for it. The upper border of the confidence interval represents the best-case scenario. The lower border of the confidence interval represents the worst-case scenario. The width of the interval between the best and worst-case series depends on the variability of the collected historical performance data (the greater the variability, the wider the interval).
This is true for the “floor” threshold only (Datastore Free Space). For the “ceiling” thresholds (Datastore Provisioned Space, Datastore Max Device Read Latency, Datastore Max Device Write Latency) upper border will represent the worst-case scenario.
- Value represents the historical performance data for the data collection period (for example, how the amount of datastore free space has changed within the analyzed period)
- Threshold represents the threshold specified for the datastore resource
- Capacity represents the total datastore capacity (will be displayed only for the Free Space performance forecast chart)
The Provisioned Space, IOPS, Max Device Read and Write Latency performance forecast charts will display the Trend and its deviation, Value and Threshold types of data series for the analyzed data collection period.
The performance forecast tables will provide the following details for the datastore resources:
Name of the analyzed resource
Specified threshold value
Prediction on whether the resource threshold will be breached within the forecast period. Possible prediction values are:
Number of days left before the specified threshold is breached. The number of days is shown both for the worst-case scenario and best-case scenario.
Predicted metric value on the forecast horizon date (that is, at the end of the forecast period). The metric value is shown both for the best-case scenario and worst-case scenario.
Amount of non-consumed resources on the forecast horizon date (that is, at the end of the forecast period):
The amount of available resources is calculated as the difference between the specified threshold value and the metric forecast value. Positive values mean that spare resources will be available. Negative values mean that extra resources are required to survive
The values are shown both for the best-case scenario and worst-case scenario.