evaluationPeriods

The number of most recent periods over which data is compared to the specified threshold. If you are setting an "M out of N" alarm, this value (evaluationPeriods) is the N.

If you are setting an alarm that requires that a number of consecutive data points be breaching to trigger the alarm, this value specifies the rolling period of time in which data points are evaluated.

Each evaluation period is five minutes long. For example, specify an evaluation period of 24 to evaluate a metric over a rolling period of two hours.

You can specify a minimum valuation period of 1 (5 minutes), and a maximum evaluation period of 288 (24 hours).