In this paper we implement the EDF-VD (Earliest Deadline First with Virtual Deadline) algorithm described in [1] for scheduling mixed-criticality, realtime task systems on preemptive uniprocessor platforms. We compare the scheduling overheads of this algorithm with the scheduling overheads of the well known EDF (Earliest Deadline First) algorithm for scheduling realtime task systems on preempti...

We present a method for calculating the minimum EDF-feasible deadline. The algorithm targets periodic tasks with hard real-time guarantees, that are to be feasibly scheduled with EDF (Earliest Deadline First). The output is the smallest possible deadline required for feasibility, of the task most recently requested. The good thing with our algorithm is that it has the same timecomplexity as the...

Earliest deadline first (edf) is a widely used algorithm for online deadline scheduling. It has been known for long that edf is optimal for scheduling an underloaded, single-processor system; recent results on the extra-resource analysis of edf further revealed that edf when using moderately faster processors can achieve optimal performance in the underloaded, multi-processor setting. This pape...

Future ATM networks will support real-time voice and video services and we need to guarantee cell transfer delay and cell loss probability to launch such services. The Earliest Deadline First (EDF) scheme is a suitable service scheduling scheme for these services since it has been proven that it can minimize the number of late cells by assigning deadlines to the cells. However, the EDF scheme c...

The most important requirement for real-time systems is the capability to support the timely execution of applications. Real-time scheduling over a single processor has been widely studied in the last thirty years, and it has been proven that the non-preemptive version of Earliest Deadline First (EDF) algorithm is optimal [1], in the sense that if a set of tasks is schedulable, it is also sched...

This paper compares the behaviour of Earliest Deadline First (EDF) and Opportunistic-EDF (O-EDF) with that of Round Robin, Proportional Fair Throughput (PFT), and Maximum Carrier to Interference ratio (MaxC/I) . Video, voice and web traffic are transmitted through an HSDPA air interface. The resultant queueing delay and fairness are measured and compared for each scheduler.

This paper proposes a novel schedule-based approach for scheduling a continuous stream of batch jobs on the machines of a computational Grid. Our new solutions represented by dispatching rule Earliest Gap— Earliest Deadline First (EG-EDF) and Tabu search are based on the idea of filling gaps in the existing schedule. EG-EDF rule is able to build the schedule for all jobs incrementally by applyi...

This paper presents an algorithm, called Earliest Deadline Critical Laxity (EDCL), for scheduling sporadic task systems on multiprocessors. EDCL is a derivative of the Earliest Deadline Zero Laxity (EDZL) algorithm. Each job is assigned a priority based on the well-known Global Earliest Deadline First (G-EDF) algorithm, as long as its laxity – the amount of time from the earliest possible time ...

Real time system is the system where data should be processed in time. The real time data is stored in real time database within the specified time interval. This time interval is called as validity time interval [1],[2]. The validity of real time data is maintained using different scheduling algorithms. The process of maintaining the validity of real time data is done by using several update t...

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...