Scheduling: external watchdog timer
The RTXPS forward chaining inference loop runs conrinuously;
The individual interactions are driven by an externally scheduled (using system level cron) watchdog, that start the individual iterations at a (configurable) interval, depending on the complexity of the RULE base, but also the response time requirements.
The modular architecture of RTXPS will support any numnber of parallel instances of the forward chaining loops, running as parallel (staggered) threads in the system. This can take full advantage of modern multi-core CPU technology to make real-time performance and guaranteed response time near independent of system compleity.
A system of semaphores is used for coordination of shared resources (data base, web server) and tie breaks to avoid oscillations.
The use of an external (to RTXPS proper) watchdog increases systems (mission critical) reliability, but also simplifies dynamic memory management (garbage collection) and serves to avoid cumulative errors.
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