RTLinux

RTLinux is a hard real-time operating system (RTOS) microkernel that runs alongside a standard Linux kernel. It allows Linux to function as a general-purpose operating system while RTLinux handles time-critical tasks with strict determinism. In essence, RTLinux interposes itself between the hardware and the standard Linux kernel, effectively making Linux a low-priority task within the RTLinux environment.

RTLinux achieves real-time performance by inserting a small, real-time executive between the hardware interrupt controller and the standard Linux kernel. When an interrupt occurs, the real-time executive gains control first. It then determines if the interrupt is intended for a real-time task. If so, the real-time task is executed immediately. Otherwise, the interrupt is passed on to the standard Linux kernel. This interception and prioritization mechanism allows RTLinux to guarantee the execution of real-time tasks within specified deadlines.

Because RTLinux uses the standard Linux kernel, it benefits from the wealth of drivers, networking capabilities, and user applications available for Linux. This allows developers to build complex systems that combine real-time and non-real-time functionalities on a single platform.

Key characteristics of RTLinux include:

• Hard Real-Time: Provides predictable and deterministic execution of real-time tasks, meeting strict deadlines.
• Microkernel Architecture: Employs a small, specialized kernel for real-time tasks, minimizing latency and maximizing performance.
• Linux Compatibility: Runs alongside a standard Linux kernel, leveraging its functionality and resources.
• Interrupt Handling: Prioritizes interrupts, ensuring that real-time tasks are executed promptly.
• Modular Design: Allows for easy integration of real-time components into existing Linux systems.

RTLinux is used in a wide range of applications, including industrial automation, robotics, data acquisition, and embedded control systems. It offers a powerful and flexible solution for developers who need to combine the benefits of a general-purpose operating system with the strict timing requirements of real-time applications.