With the development of cloud computing, mobile device and industry automation, virtualization plays an important role today. The core of virtualization is hypervisor which directly determines the performance of platform. Therefore, how to allocate resource effectively becomes an important issue. Xen, one of widely used open source projects, is a virtual machine monitor. Simple EDF (Earliest De...

Earlier studies have observed that in moderately-loaded real-time systems, using an earliest deadline policy to schedule tasks results in the fewest missed deadlines. However, when the real-time system is overloaded an earliest deadline schedule performs worse than most other policies. This is due to the earliest deadline giving the highest priority to the tasks that are close to missing their ...

To this paper we have study to Reduce the time Complexity of Earliest Deadline First (EDF), a global scheduling scheme for Earliest Deadline First in Real Time System tasks on a Multiprocessors system. Several admission control algorithms for earliest deadline first are presented, both for hard and soft real-time tasks. The average performance of these admission control algorithms is compared w...

We present a general purpose model and schedulability condition for supporting multiple service classes using bandwidth resource partitioning. The model supports guaranteed communication performance for real-time multimedia tra c via an Earliest Deadline First (EDF) packet transmission policy. We show how the EDF model can incorporate the e ect of multiple service classes sharing the same trans...

Consider the problem of scheduling sporadically-arriving tasks with implicit deadlines using Earliest-Deadline-First (EDF) on a single processor. The system may undergo changes in its operational modes and therefore the characteristics of the task set may change at run-time. We consider a well-established previously published mode-change protocol by Sha et al. and we show that if every mode uti...

Time constraint is the main factor in real time operating system and it affects the deadline of the process. To achieve deadline, proper scheduling algorithm is required to schedule the task. In this paper an Adaptive scheduling algorithm is developed which is the combination of Earliest Deadline First (EDF) and Ant Colony Optimization (ACO). The EDF algorithm places the process in a priority q...

The real time data is stored in real time database. To maintain the temporal validity of real time data different real time scheduling algorithms are used. The valid data is further used for different operations in real time sensing and control system or in process control applications. The real time data values are stored in real time database at every instant of time. So previous data value b...

This paper presents a network with earliest deadline first (EDF) scheduling on a per slot basis. The network is called CCR-EDF (Control Channel based Ring network with EDF scheduling). The topology is a pipelined unidirectional fibre-ribbon ring that supports several simultaneous transmissions in non-overlapping segments and with dedicated fibres for clock and arbitration. In each slot the node...

This paper presents work on a switched Ethernet network extended to allow for earliest deadline first (EDF) scheduling. We show by example that asymmetric deadline partitioning between the links of a real-time channel can increase the utilization substantially, still not violating the real-time guarantees. We also report measurements on a software implementation of the switch on an ordinary PC.