Threshold

A severity of a particular type is trigged whenever the returned value from the check is higher than the configured threshold, the baseline.

The notification threshold / baseline can be defined in several ways.

Settings

Setting	Description
Method	Constant / Average / Median / Deviation
Percentage	Percentage threshold based on the calculated value.
Deviation	Number of standard deviations
Period	Time period for historical results to include in the calculation.
Offset	Constant to add to the calculated value.

Calculations

Static calculations uses a constant threshold value.

Dynamic methods calculate the threshold value on the fly, based on a combination of the type (percentage or deviation), the method (average, median, deviation), the period (time frame for historical data to use), and offset which is added to the calculated value.

Method	Calculation	Type	Example
Constant	A fixed value.	Static	25
Average	Average.	Dynamic	120% of the average returned value for the last 2 hours + offset 50.
Median	Median.	Dynamic	120% of the median value for the last 2 hours + offset 50.
Deviation	Standard deviation.	Dynamic	2 standard deviations + average value for the last 2 hours + offset 50.