Hybrid Metaheuristic Approach for Scheduling of Aperiodic OS Tasks - Complex System Modelling and Control Through Intelligent Soft Computations - page 845

selection (to run next) and its deletion would require O(n) time, where n is the
number of tasks in the queue. When a task arrives, a record for it can be inserted into
the heap in O(log(n)) time where n is the total number of tasks in the priority queue.
Therefore, the time complexity of our hybrid algorithm is equal to that of a typical
sorting algorithm which is O(n log(n)). So O(nlog(n)) time is required. Finally, for
both the polling server and the background server in our hybrid scenario approach
performs best and yield improved average response times for aperiodic requests and
the most important results are presented in our work. So, we can deduce that using
our proposed approach under such conditions may be advantageous.

5 Conclusion and Future Works

In this topic chapter, we propose a new theory for the minimization of the response
time of aperiodic real-time tasks with the polling server and the background server
that can be applied to uniprocessor systems and proved it correct. We showed that
this theory is capable to recon

gure the whole system. Previous work in this area
has been described, several and best solution has been suggested. This hybrid
solution is primarily intended to reduce the processor demand and the response time
of each task set independent of the number of tasks in a uniprocessor system. A tool
is developed and tested to support all these services.
At the end, we present a few inadequacies and propose directions of research to
extend our study to the case of distributed systems and, we plan also to apply this
contribution to other complex recon gurable systems that we have chosen to not

cover in this topic chapter. We hope that this work will serve as a good starting
point and a useful reference for researchers working on the development of real-
time scheduling approches of aperiodic tasks in embedded systems.

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