pocketmine\Server::tickProcessor PHP Method

    private function tickProcessor()
    {
        $this->nextTick = microtime(true);
        while ($this->isRunning) {
            $this->tick();
            $next = $this->nextTick - 0.0001;
            if ($next > microtime(true)) {
                try {
                    time_sleep_until($next);
                } catch (\Throwable $e) {
                    //Sometimes $next is less than the current time. High load?
                }
            }
        }
    }