With automation spanning virtually every sector of society, real-time capable operating systems (OS) are becoming critical across industries, from automotive and telecommunications, to industrial manufacturing. A real-time operating system (RTOS) ensures precise and deterministic responses, meeting strict timing requirements essential for safety and performance. But is a traditional RTOS, like Zephyr or FreeRTOS, the right choice for your business, or would a Linux solution with real-time capabilities better suit your needs?
Our latest whitepaper provides an in-depth exploration of these questions, and in this blog we’ll cover the top level overview.
What makes a system “real-time”?
Real-time systems prioritize timing over raw performance. They are designed to handle specific tasks within strict time constraints. Unlike general-purpose systems, where overall throughput is taken into consideration, real-time systems focus on deterministic outcomes, as every operation must occur predictably within defined limits. This determinism is essential for applications like vehicle safety mechanisms, industrial control systems, and telecom infrastructure. In the next section, we’ll assess a few key considerations when comparing a “hard” RTOS or Linux with real-time capabilities. For a more thorough analysis, please refer to the latest whitepaper.
An RTOS is purpose-built for environments where missing deadlines could result in catastrophic failure. With low overhead, RTOSs ensure predictable task scheduling, making it ideal for mission-critical scenarios like medical devices or aerospace control systems. However, its highly specialized nature limits scalability and flexibility.
Real-time Linux, particularly with the PREEMPT_RT patchset, extends Linux’s capabilities by improving task prioritization and reducing latency. While it may not achieve the strict determinism of a traditional scheduler or RTOS in ultra-critical applications, it provides sufficient real-time performance for many use cases. This makes it versatile for projects that blend real-time requirements with broader operational needs.
Furthermore, Linux’s open-source nature offers extensive hardware compatibility, a rich suite of debugging tools, and an active developer community. In contrast, a proprietary RTOS often requires custom development and lacks robust driver infrastructure, potentially increasing time-to-market.
Finally, it is worth mentioning that building and maintaining an RTOS requires substantial in-house expertise. Real-time Linux solutions often offer long-term support (LTS) – for example, Real-time Ubuntu provides up to 12 years of support – to ensure reliability, security updates, and reduced operational overhead for enterprises.
From factory automation and industrial control to low latency for telco infrastructure, there is a need to ensure responsiveness and deterministic behavior for workloads that require time-sensitive computing. The next section will clarify how a real-time OS is used to satisfy those time-bound applications across verticals.
Use cases across industries
Real-time capable OSes find use across a wide range of industries, including process automation (energy sector, petroleum, refineries) and discrete automation (car manufacturing). Furthermore, healthcare, factories, telco networks, automotive, aviation, and more, often demand real-time compute capabilities. Real-time is also used in product quality assurance, safety, oil and gas, and transportation systems with strict precision requirements for automation. Let’s take a look at some specific examples.
Automotive
Real-time systems are critical for safety features like anti-lock braking systems and autonomous driving. While RTOSs have traditionally dominated in ECUs, Linux is increasingly used for infotainment and vehicle-to-everything (V2X) applications due to its scalability and support for diverse hardware.
Telecommunications
Telecom networks demand ultra-low latency for applications like 5G infrastructure. Real-time Ubuntu supports virtualized Radio Access Networks (vRAN) and OpenRAN, enabling efficient resource allocation and high-performance network functions.
Industrial automation
Factories rely on deterministic computing to manage assembly lines and control systems. Real-time Ubuntu, combined with Time Sensitive Networking (TSN) and Intel Time Coordinated Computing (TCC), offers precise synchronization for industrial applications.
Making the right choice
Real-time systems ensure precise and reliable operations in critical environments, and effectively utilizing these technologies can help you optimize performance, reduce costs, and accelerate your time-to-market. Whether RTOS or real-time Linux is the better fit for your use case will depend on your specific requirements, but it broadly comes down to the following rule of thumb:
- For systems that are extremely latency sensitive, RTOS provides the highest degree of consistency and determinism.
- In mixed-criticality environments requiring both real-time capabilities and broader OS functionalities, real-time Linux with PREEMPT_RT offers superior versatility and supportability.
For a more detailed look at RTOS and real-time Linux, and additional guidance on choosing the right option for your organization, access the full whitepaper.
https://ubuntu.com/engage/real-time-os-whitepaper
