public function activateOnQueue()
    {
        // if it's an immediate job, lets cache it to disk to be picked up later
        if ($this->JobType == QueuedJob::IMMEDIATE
            && !Config::inst()->get(QueuedJobService::class, 'use_shutdown_function')
        ) {
            touch($this->getJobDir() . '/queuedjob-' . $this->ID);
        }
    }