Industry 4.0 is coming and production lines need new technologies to deal with customers that increasingly ask for new features. From the computer technology perspective, the trend goes toward the use of single board computers equipped with Embedded Linux for dealing with many functionalities required. In this scenario, where most of the industrial control systems need real-time performance, developers have to deal with the fact that Linux was not meant to be used in real-time situations. However, over the years, many have been the attempts of making Linux working real-time, and today the most common solution named PREEMPT_RT helps to gain some real-time capabilities.