How to increase boot up speed?

During bootup in Apalis-iMX6_Qt4-X11-Image 2.7.3 (A start job is running for…o be Configured )this is taking 30 seconds to start a service how to optimize the boot speed by starting that service fast

In case of deep optimization you can get boot time below 1. sec. You can see a video here.
https://www.toradex.com/videos/fast-boot-demo-with-linux-and-qt

Please follow these articles:

http://blog.qt.io/blog/2016/04/20/fast-booting-qt-devices-part-1-automotive-instrument-cluster/
http://blog.qt.io/blog/2016/04/27/fast-booting-qt-devices-part-2-optimizing-qt-application/
http://blog.qt.io/blog/2016/05/25/fast-booting-qt-devices-part-3-optimizing-system-image/
http://blog.qt.io/blog/2016/08/30/fast-booting-qt-devices-part-4-hardware-matters/