Tasks of an application program of an embedded system are managed by the scheduler of a real-time operating system (RTOS). Most RTOSs adopt just fixed priority scheduling, which is not optimal in all cases. Some applications require earliest deadline first (EDF) scheduling, which is an optimal scheduling algorithm. In order to develop an efficient real-time embedded system, the scheduling algor...

Deadlines are the most important events in real-time systems. Realtime programs must therefore be aware of deadlines, and be able to identify and react to missed deadlines. Moreover, Earliest Deadline First (EDF) is the most widely studied optimal dynamic scheduling algorithm for uniprocessor real-time systems. In this paper we explore how a resource sharing protocol (called the DFP – Deadline ...

In this paper we present the utilization bound for Earliest Deadline First (EDF) scheduling on homogeneous multiprocessor systems with partitioning strategies. Assuming that tasks are pre-emptively scheduled on each processor according to the EDF algorithm, and allocated according to the First Fit (FF) heuristic, we prove that the worst-case achievable utilization is 0:5(n + 1), where n is the ...

This paper reports on our on going empirical evalu ation of a two tiered resource allocation scheme assum ing independent jobs that is jobs have no precedence constraints The rst tier extends the temporal density approach load balancing within a time interval while the second tier uses variations of the Earliest Deadline First EDF approach to schedule jobs at a site However job scheduling at si...

BACKGROUND AND PURPOSE To specify a simple conversion of neurophysiological signals contained in sleep recordings into standard audio files and to illustrate how our cerebral audio processor can then detect specific signal characteristics. METHODS A software package (freely accessible from the Internet) has been developed that converts signals from standard EDF (or EDF+) format to standard au...

This report shows how to tighten the analysis of global EDF scheduling on multiprocessor platforms, so as to verify the feasibility of a significantly larger range of task systems than has been possible using the previously known tests, including those recently by Bertogna, Cirinei, and Lipari. The improved EDF feasibility test for sporadic task systems with arbitrary deadlines is proven correc...

The core of virtualization is hypervisor which directly determines the platform performance. How to allocate resource effectively becomes an important problem. Xen is an open source hypervisor and used as a virtual machine monitor. In this paper, we designed an efficient virtual CPU scheduling algorithm that combined Deadline-Monotonic Scheduling with Simple Earliest Deadline First (EDF) schedu...

Energy conservation has become a critical problem for real-time embedded storage systems. Although a variety of approaches to reducing energy consumption has been extensively studied, energy conservation for real-time embedded storage systems is still an open problem. In this paper, we propose an energy management strategy (IBEC) using I/O burstiness for real time embedded storage systems. Our ...

Fiber-based multi-wavelength lasers have a variety of important applications in telecommunication and meteorology. We experimentally study fiber loop laser with an integrated Erbium doped (EDF). The output optical spectrum is measured as function the EDF temperature. find that below critical temperature about exhibits sequence narrow unequally-spaced peaks. An intriguing connection between peak...

Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes ðs tÞ units of execution. The earliestdeadline-first (EDF) scheduling of hard-real-time systems upon uniform multiprocessor machines is considered. It is known that online algorithms tend to perf...