SpringBoot中定时任务默认是串行执行 如何设置并行

@EnableScheduling
@EnableAsync
@SpringBootApplication
public class App
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );

        SpringApplication app = new SpringApplication(App.class);
        //关闭banner
        app.setBannerMode(Banner.Mode.OFF);
        app.run(args);
    }
}

@Service
@Async
public class TaskSecond {

    private Logger logger = LoggerFactory.getLogger(TaskSecond.class);
    //@Scheduled( cron = "0/2 * * * * * ")
    @Scheduled(fixedDelay = 20000,initialDelay = 2000)
    public void test(){
        try {
            logger.info(" second start");

            TimeUnit.SECONDS.sleep(10);
           logger.info(" second end");

        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

@Service
@Async
public class TaskFirst {
    private Logger logger = LoggerFactory.getLogger(TaskSecond.class);
    //@Scheduled( cron = "0/2 * * * * * ")
    @Scheduled(fixedDelay = 20000,initialDelay = 2000)
    public void test(){
        try {
            logger.info(" first start");

            TimeUnit.SECONDS.sleep(10);
            logger.info(" first end");

        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}