Microsoft open-sources ThreadX
Microsoft has released its ThreadX real-time operating system under an open-source (MIT) license and handed stewardship to the Eclipse Foundation, prompting debate over whether this will revitalize a widely deployed but previously proprietary RTOS or let it stagnate in bureaucracy. Commenters highlight ThreadX’s massive embedded footprint, safety certifications, and its strategic role versus Amazon’s FreeRTOS, while noting that open-sourcing the core still won’t unlock closed GPU firmware such as Raspberry Pi’s VideoCore. Many see the move as a net win for embedded and safety-critical systems, provided ongoing funding and recertification work materialize.
Eclipse ThreadX Open-Sourcing & Licensing
- Many see open-sourcing ThreadX as a clear win versus keeping it proprietary, especially given its huge deployment base.
- Some worry Eclipse Foundation governance is slow/bureaucratic and may let projects stagnate, but others note anyone can fork if progress stalls.
- There is confusion about licensing: existing GitHub repo still shows an evaluation/limited-hardware license, but announcements say it’s moving to MIT. Several commenters treat MIT as the intended final state and expect repo updates.
Strategic Context: Microsoft, AWS, FreeRTOS
- ThreadX (rebranded as Azure RTOS) was acquired after Amazon bought FreeRTOS; commenters view Microsoft’s move to Eclipse as effectively stepping back from that IoT-RTOS strategy.
- Multiple posts argue Amazon bought FreeRTOS to drive AWS IoT lock-in and automotive/“software-defined vehicle” workloads; Microsoft is seen as having followed rather than led.
- Some are uneasy about big-cloud control of core RTOSes, but others think the main benefit is more mature SDKs and tooling.
Safety Certification & Industry Impact
- A major theme is that ThreadX already carries safety certifications (e.g., automotive, rail). Maintaining these under an open model is seen as expensive but potentially “industry changing.”
- Certification is described as process-heavy, with ongoing costs and re-certification for changes; still, starting from a certified base is considered a big advantage.
- Debate over whether certification acts as a control point: you can freely modify the code, but you lose the certified status unless you re-certify. Consensus: this constrains everyone equally, including Microsoft, but Microsoft likely has cheaper recert paths.
Comparisons to Other RTOSes
- ThreadX is characterized as very small and focused: essentially a scheduler plus threading/memory/IPC primitives.
- Zephyr is seen as more feature-rich (better board support, testing infrastructure) but more complex and still working toward safety certification.
- FreeRTOS is widely used but not itself safety-certified; a commercial derivative (SAFERTOS) exists for that space.
- Other RTOSes mentioned as now-open include µC/OS-II/III; QNX is noted as separate (owned by BlackBerry) and not affected.
Raspberry Pi, VideoCore, and GPU Firmware
- Strong interest in ThreadX because it underpins Raspberry Pi’s VideoCore boot firmware, which controls the hardware and treats the ARM cores as “slaves.”
- Some hope this will lead to an open-source release of the Pi’s GPU firmware; others argue this is unlikely due to separate Broadcom IP, DRM, and patent risks.
- A clean-room open firmware for Pi already exists; commenters say ThreadX’s source is largely irrelevant to that effort.
Embedded & Historical Notes
- Several posts recount long prior use of ThreadX in printers, cameras, management engines, and other deeply embedded systems.
- There’s discussion of how far embedded FOSS tooling has come, and how RTOSes are typically minimalist and often not proprietary anymore.
- A side debate covers Linux vs MINIX history and what counts as a “fork,” illustrating some confusion but not impacting the ThreadX topic.