public function captureStart(EventInterface $event)
    {
        ++$this->index;

        $time = microtime(true);

        $eventName = $event->getName();
        if ($eventName) {
            $this->timers[$eventName] = ['start' => $time, 'stop' => $time];

            return;
        }
        $this->timers[$this->index] = ['start' => $time, 'stop' => $time];
    }