Examples of formulas and parameters in custom Optimizer rules

You can define a formula to generate alerts and recommendations from a custom Optimizer rule. And, you can define parameters to be used in the formula.

Adding custom Optimizer rules based on formulas is intended for advanced users only.

Examples of formulas

The following table contains some examples of formulas that you can add to the Formula field in the Condition section of a custom Optimizer rule.

Goal	Example of formula
To generate an alert on overprovisioned datastores based on metric values (DSTORE_PROVISIONED is greater than DSTORE_SIZE)	alerted = (DSTORE_PROVISIONED.value > DSTORE_SIZE.value);
To know if data for an indicator/metric (IND_DAYS_TO_SATURATION) is available	if (IND_DAYS_TO_SATURATION) { ... }
To get an indicator (IND_DAYS_TO_SATURATION) value	IND_DAYS_TO_SATURATION.value
To get a specific subresource value, for example CPU	IND_DAYS_TO_SATURATION.subresource("CPU").value;
To know if data for a certain subresource is available, for example CPU	if (IND_DAYS_TO_SATURATION.hasSubresource("CPU")) { ... }
To set a value or threshold in the output	point.value0 = some_value; point.threshold0 = a_threshold; ...; point.value20 = some_value; point.threshold20 = a_threshold;
To add a resource to an alerted subresource, for example CPU	point.addAlertedResource("CPU");
To generate an alert when the days to saturation for CPU, memory, or storage is more than the threshold value	var res = false; if(Math.round(IND_DAYS_TO_SATURATION.value)<=30) { if(IND_DAYS_TO_SATURATION.hasSubresource("CPU") && IND_DAYS_TO_SATURATION.subresource("CPU").value<30) { res = true; } if(IND_DAYS_TO_SATURATION.hasSubresource("MEMORY") && IND_DAYS_TO_SATURATION.subresource("MEMORY").value<30) { res = true; } if(IND_DAYS_TO_SATURATION.hasSubresource("STORAGE") && IND_DAYS_TO_SATURATION.subresource("STORAGE").value<30) { res = true; } } alerted = res;

Screenshot with sample data

Examples of parameters

Parameters must be inserted as per the following syntax:

Where <type> can be a number or a string.

To add more than one parameter to your custom rule, separate them with a newline character (press Enter) in the Parameters section. You can add as many parameters as you like.

Parameters are commonly used to define new thresholds that can be used in formulas.

The following table contains some examples of parameters that you can add to the Parameters field in the Condition section of a custom Optimizer rule.

Goal	Parameter definition
To create a threshold: Days to saturation – Critical threshold, set to a value of 7 (days)	dts_th_crit\|Days to saturation critical threshold\|7\|number
To create a threshold: Days to saturation – Warning threshold, set to a value of 30 (days)	dts_th_warn\|Days to saturation warning threshold\|30\|number

Screenshot with sample data

Example of using parameters in formulas

The following table contains some examples of parameters that are used in a formula in a custom Optimizer rule.

Goal	Parameter definition
To the following thresholds in the formula: dts_th_crit\|Days to saturation critical threshold\|7\|number dts_th_warn\|Days to saturation warning threshold\|30\|number	var res = false; var dts_th = Math.max(dts_th_crit, dts_th_warn); if (IND_DAYS_TO_SATURATION.value <= dts_th) { res = true; }

Screenshot with sample data

Example of recommendation text in a custom Optimizer rule

Example of recommendation text or description using a Velocity template

The following code block illustrates an example of a Velocity template description that you can add to the Recommendation text field in the custom Optimizer rule. This field is displayed only after you select an option in the Recommendation type list.

#if ( $point.value0>0) Forecasted saturation in $numberFormatter.format($point.value0) days. #else Some resources are already saturated. #end
Details:
#if ($point.alertedResources.contains('CPU'))
  #if ($point.value1>0) CPU will saturate in $numberFormatter.format($point.value1) days.
  #else CPU exhausted.
  #end
#end
#if ($point.alertedResources.contains('MEMORY'))
  #if ($point.value2>0) Memory will saturate in $numberFormatter.format($point.value2) days.
  #else Memory exhausted.
  #end
#end
#if ($point.alertedResources.contains('STORAGE'))
  #if ($point.value3>0) Storage will saturate in $numberFormatter.format($point.value3) days.
  #else Storage exhausted.
  #end
#end

Screenshot with sample data

You can use formatting functions that the Velocity template provides in the Recommendation text field. The following table illustrates some of these formatting functions.

Structure of a recommendation output

A recommendation output is structured as follows (split into 2 lines only for illustration purposes):

alert.cond.1.rule.recomm.vtl =
Allocate more $stringFormatter.formatList($point.alertedResources)

Setting a status for alerts in the recommendation output

To set a critical status for an alert, you must set the severity as per the ALERT_STATUS table.

For example, to generate a Critical alert whose ID is 3, the structure is as follows:

alert.cond.1.severity = 3

Examples of formulas and parameters in custom Optimizer rules