src/Web/Sessions/SessionHandlerAbstract.php
protected function createGcTimer()
    {
        if (isset($this->_timer) && $this->_timer instanceof TimerInterface) {
            $this->loop->cancelTimer($this->_timer);
        }
        $this->_timer = $this->loop->addPeriodicTimer($this->timerInterval, [$this, 'gc']);
    }
protected function createGcTimer()
    {
        if (isset($this->_timer) && $this->_timer instanceof TimerInterface) {
            $this->loop->cancelTimer($this->_timer);
        }
        $this->_timer = $this->loop->addPeriodicTimer($this->timerInterval, [$this, 'gc']);
    }
Create GC periodic timer