src/Google/Task/Runner.php
private function getDelay()
  {
    $jitter = $this->getJitter();
    $factor = $this->attempts > 1 ? $this->factor + $jitter : 1 + abs($jitter);

    return $this->delay = min($this->maxDelay, $this->delay * $factor);
  }
private function getDelay()
  {
    $jitter = $this->getJitter();
    $factor = $this->attempts > 1 ? $this->factor + $jitter : 1 + abs($jitter);

    return $this->delay = min($this->maxDelay, $this->delay * $factor);
  }
Gets the delay (in seconds) for the current backoff period.

@return float