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Real-Time Kernel Options

Not all use cases require a real-time OS, please read below to determine if you need it.

⚙️ Kernel Options for Real-Time Performance

Ubuntu offers multiple kernel variants tailored for different workloads:

Kernel Type Description Typical Use Case
generic Default kernel: balanced performance & power management General desktop/server use
lowlatency Reduced interrupt latency; better scheduling responsiveness Robotics, audio processing, soft real-time
rt (PREEMPT_RT) Fully preemptible; hard real-time determinism Industrial control, mission-critical systems

⚠️ Important Disclaimer

Upgrading to a low-latency or real-time (RT) kernel may: - Break proprietary drivers (e.g., NVIDIA, Wi-Fi modules) - Cause system instability or boot failure

You assume full responsibility for any issues arising from kernel changes.
✅ Always back up your system before proceeding.

Install Low-Latency or PREEMPT_RT Kernel for Ubuntu/x84-64

Option 1: Low-Latency Kernel

  1. Install the kernel: For Hardware Enablement (HWE) stack (check with uname -r; e.g., Ubuntu 22.04 with kernel 6.x), use:

bash sudo apt update && sudo apt install --install-recommends linux-lowlatency-hwe-22.04 # replace "22.04" with your version For the original kernel (5.15), use: bash sudo apt update && sudo apt install --install-recommends linux-lowlatency

  1. Set GRUB to prefer low-latency: bash echo 'GRUB_FLAVOUR_ORDER="lowlatency"' | sudo tee -a /etc/default/grub sudo update-grub

  2. Reboot and verify: bash sudo reboot uname -r # Should show "...-lowlatency"

🔄 To revert to generic, change GRUB_FLAVOUR_ORDER="generic" and run sudo update-grub.

Option 2: PREEMPT_RT Kernel

Ubuntu releases listed in this page have native real-time kernel support, and can be easily enabled via a few commands, see full tutorial at https://ubuntu.com/real-time.

ℹ️ Ubuntu 22.04/24.04 users can enable RT kernel via free Ubuntu Pro subscription. The subscription is free for personal use.

ℹ️ For Nvidia Jetson(arrch64), please refer to Nvidia's official documentation.