- Linux is multiuser, timesharing system
- Kernels up until 2.4 are not preemptible (2.5 started to integrate low latency and kernel preemption patches)
- The current 2.6 kernels include major parts of the rt-reempt patchset
but still no hard realtime.
- Alternatives are
- rt-preempt patch
- Dual kernel approach
- RTAI (Paolo Montegazza) is GPLd
- RT-Linux (Victor Yodaiken FSM Labs) is patented . Not clear if patent would stand up in court.
- Two-level structure is faster but more complicated
|4.4. Real-time Linux||1. Denx Training Topics||4.4.2. Real time with Adeos/Xenomai (Introduction)|