question: public static boolean isWithinTimeComparisonEpsilon ( long timeMicros ) { long now = Utils . getSystemNowMicrosUtc ( ) ; return Math . abs ( timeMicros - now ) < timeComparisonEpsilon ; }
target:  Compares a time value with current time. Both time values are in micros since epoch. Since we can not assume the time came from the same node, we use the concept of a time epsilon: any two time values within epsilon are considered too close to globally order in respect to each other and this method will return true.