private synchronized boolean missedStartTime() {
    return isValidTime(timeOfLastRun) && isValidTime(timeOfThisRun)
      && getTimeBetweenRuns() > getMaximumAllowedTimeBetweenRuns();
  }
Returns true when the time between runs exceeds the acceptable threshold
hbase-common/src/main/java/org/apache/hadoop/hbase/ScheduledChore.java