rules/recording.go
func (rule *RecordingRule) SetEvaluationDuration(dur time.Duration) {
	rule.mtx.Lock()
	defer rule.mtx.Unlock()
	rule.evaluationDuration = dur
}
func (rule *RecordingRule) SetEvaluationDuration(dur time.Duration) {
	rule.mtx.Lock()
	defer rule.mtx.Unlock()
	rule.evaluationDuration = dur
}
// SetEvaluationDuration updates evaluationDuration to the time in seconds it took to evaluate the rule on its last evaluation.