Real-time Ubuntu

Real-time Ubuntu is Ubuntu with a real-time kernel.

Ubuntu’s real-time kernel includes the PREEMPT_RT patchset. It changes Linux’s default scheduler to a priority-based one, increasing predictability by modifying the existing kernel code. Real-time Ubuntu is more pre-emptive than mainline, delivering determinism and lower latency.

Stringent applications have mission-critical latency requirements and must ensure high-priority processes are executed first, with deterministic response times. Real-time Ubuntu provides an upper bound on execution time, to the most demanding workloads in industrial, telco, automotive, and robotics applications.

From assembly lines processing and delivering data in real-time to ensure system integrity to critical telco infrastructure operating at low latency for continuous production, the most exacting applications run on Real-time Ubuntu.

In this documentation


Start here: a hands-on introduction to Real-time Ubuntu for new users.


Step-by-step guides covering key operations and common tasks, such as installing the real-time kernel and configuring the CPUs.


Technical information about metric tools, boot parameters and supported releases.


Conceptual information about Linux kernel schedulers.

Project and community

The Real-time Ubuntu project welcomes community contributions, suggestions, fixes and constructive feedback. If you wish to contribute to the Real-time Ubuntu docs, consult the CONTRIBUTING guide.

Before raising a pull request, it’s generally worth opening an issue to discuss any proposed change unless it’s trivial. Then, if you decide to raise a pull request, be sure you’ve signed the Canonical contributor agreement — it’s the easiest way to grant us permission to use your contributions.