PREEMPT_RT was a set of patches for the Linux kernel which implement both hard and soft real-time computing capabilities.[1] On September 20, 2024, PREEMPT_RT was fully merged and enabled in mainline Linux on the supported architectures x86, x86_64, RISC-V and ARM64.[2] This will make kernel v6.12 the first release to include baked-in real-time capability.
History
editThe PREEMPT_RT patchset has been in development since 2005.[3] In 2021, the preemption core locking code was merged.[4][5]
Since February 2023, Canonical has been releasing real-time versions of Ubuntu Pro, free for personal and small-scale commercial use in up to 5 machines.[6][7] The real-time kernel can be added to various existing Ubuntu releases through an enablement process.[7] These kernels include the PREEMPT_RT patchset and offer long-term support.[7]
MontaVista Software has been releasing a real-time Linux distribution containing the PREEMPT_RT patchset since the early 2000. Montavista's current main embedded Linux product, CGX, contains real-time preemption as a standard feature.
At the Sep. 2024 European Open Source Summit, Linus Torvalds announced that PREEMPT_RT had been accepted into the mainline linux kernel after a protracted development hurdle involving the printk kernel logging facility.
References
edit- ^ "20 years later, real-time Linux makes it to the kernel - really". zdnet.com. Retrieved 2024-09-19.
- ^ "Merge tag 'sched-rt-2024-09-17' - kernel/git/torvalds/linux.git - Linux kernel source tree". git.kernel.org. Retrieved 2024-09-20.
- ^ Reghenzani, Federico; Massari, Giuseppe; Fornaciari, William (2019-02-21). "The Real-Time Linux Kernel: A Survey on PREEMPT_RT". ACM Computing Surveys. 52 (1): 18:1–18:36. doi:10.1145/3297714. hdl:11311/1076057. ISSN 0360-0300.
- ^ "Realtime preemption locking core merged [LWN.net]". lwn.net. Retrieved 2023-02-09.
- ^ "The future of realtime Linux". LWN.net. Retrieved 2023-02-09.
- ^ Proven, Liam. "Real-time Ubuntu 22.04: What you need to know". The Register. Retrieved 2023-02-20.
- ^ a b c "Canonical releases Real-time Ubuntu 24.04 LTS". Ubuntu. Retrieved 2024-07-03.