code: func DurationMinusBufferDomain(intv time.Duration, buffer time.Duration, jitter int64) (min time.Duration, max time.Duration) {
  	max = intv - buffer
  	if jitter == 0 {
  		min = max
  	} else {
  		min = max - time.Duration(int64(max)/jitter)
  	}
  	return min, max
  }
docs: // DurationMinusBufferDomain returns the domain of valid durations from a
  // call to DurationMinusBuffer.  This function is used to check user
  // specified input values to DurationMinusBuffer.