Back in 2006, Linus Torvalds said, "Controlling a laser with Linux is crazy, but everyone in this room is crazy in his own way. So if you want to use Linux to control an industrial welding laser, I have no problem with your using PREEMPT_RT." The debate on whether Linux should be a real-time operating system was on.
Real-time Linux started years earlier when academics created the first real-time Linux distros such as e KURT, University of Kansas; RTAI, University of Milano; and RTLinux, New Mexico Institute of Mining and Technology. As the years went by, PREMPT-RT, which is maintained by Steven Rostedt, a Red Hat principal software programmer, became the most important real-time Linux variant.
Disagreements on how to implement real-time functionality into Linux still exist. So The Linux Foundation, the non-profit organization dedicated to accelerating the growth of Linux and collaborative development, and its allies created the new Real-Time Linux (RTL) Collaborative Project.
RTL is built on the foundation of the Open Source Automation Development Lab (OSADL). This group under the leadership of Thomas Gleixner and Ingo Molnar periodically upstream the project's RT-Preempt patches to mainstream Linux. Now, the project will be under the control of RTL.
According to The Linux Foundation, "RTL will bring together industry leaders and experts to advance and maximize technologies for the robotics, telecom, manufacturing, aviation, medical industries" and stock exchanges.
The RTL kernel also has the advantage of supporting the largest range of architectures of any real-time Linux. It can also leverage Linux device drivers, file systems and more from the mainline kernel. Real-time properties make it possible to control robots, data acquisition systems, manufacturing plants and other time-sensitive instruments and machines from RTL applications. It provides the critical infrastructure for some of the world's most complex computing systems.
Google is the founding RTL's Platinum member. Gold members include National Instruments, OSADL and Texas Instruments; and silver members include Altera, ARM, Intel and IBM. Gleixner, who has been maintaining the RTL branch for more than a decade, will become a Linux Foundation Fellow to dedicate even more time to his work on RTL.
Red Hat, however, is not an RTL member. The company did not reply to requests asking about this matter.
"The work we've been doing on Real-Time Linux has been critical in advancing complex real-time computing systems. But technology is moving fast, and the RTL project, with support from across the industry, will allow us to sustain this work and successfully integrate with the mainline kernel for long-term support of these technologies," said Gleixner in a statement.
The RTL Collaborative Project will focus on pushing critical code upstream to be reviewed and eventually merged into the mainline Linux kernel where it will receive ongoing support. The Project will conduct a quarterly code plan review, meet face-to-face at least twice a year at Embedded Linux Conference and contribute to testing and documentation of the project.