Hi On 4/5/07, Pradeep <pradeep.annavarapu@xxxxxxxxxxx> wrote:
> Hi, > > Why is Linux kernel considered a (hard) realtime OS? I already Linux kernel is never considered a real time OS. A real time OS should be predictable.The general linux kernel is not predictable because of many reasons.
To ellaborate more, any RTOS HAS TO be deterministic , i.e, it should have a deterministic latecy, a predictable jitter which will never cross its threshold even during heavy loads.
> What stops us from classifying kernel as hard RTOS? Is it because at An RTOS is just a facilitator to build Real time systems. A Real time system developer should analyse a RTOS wether is will be useful for his system. If some body is holding spin lock and making it non-preemptive its a bad design. So even a RTOS linux has spin locks. Its the designer who should take care.
Basically , a GPOS (General Purpose OS) is build to optimize the average-response time. Whereas, an RTOS is designed to optimize the worst-case response time. Hence non-RT tasks, in case of an RTOS , are given the least prioirity where as the deadlines for RT tasks are not to be crossed under ANY circumstances. Thanks, Raseel. - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs
