Evaluation of Two Mixed-Criticality Scheduling Algorithm for Periodic Tasks

2014 ◽  
Vol 513-517 ◽  
pp. 1160-1164
Author(s):  
Shu Juan Huang ◽  
Yi An Zhu

Nowadays, there are two approach in mixed-criticality scheduling. One is reservations-based approach such as EDF-VD(Earliest Deadline First-Virtual Deadline) and the Other is priority-based scheduling such as OCBP(Own Criticality Based Priority). This paper compared the two mixed-criticality scheduling algorithm from three aspects. The simulation results show that EDF-VD is better than OCBP in completed tasks and the system utilization, but in unmissed deadline ratio the later owns the better.

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Rashmi Sharma ◽  
Nitin

In Real Time System, the achievement of deadline is the main target of every scheduling algorithm. Earliest Deadline First (EDF), Rate Monotonic (RM), and least Laxity First are some renowned algorithms that work well in their own context. As we know, there is a very common problem Domino's effect in EDF that is generated due to overloading condition (EDF is not working well in overloading situation). Similarly, performance of RM is degraded in underloading condition. We can say that both algorithms are complements of each other. Deadline missing in both events happens because of their utilization bounding strategy. Therefore, in this paper we are proposing a new scheduling algorithm that carries through the drawback of both existing algorithms. Joint EDF-RM scheduling algorithm is implemented in global scheduler that permits task migration mechanism in between processors in the system. In order to check the improved behavior of proposed algorithm we perform simulation. Results are achieved and evaluated in terms of Success Ratio (SR), Average CPU Utilization (ECU), Failure Ratio (FR), and Maximum Tardiness parameters. In the end, the results are compared with the existing (EDF, RM, and D_R_EDF) algorithms. It has been shown that the proposed algorithm performs better during overloading condition as well in underloading condition.


2018 ◽  
Vol 14 (4) ◽  
pp. 155014771876899 ◽  
Author(s):  
Chengjie Xu ◽  
Rei-Heng Cheng ◽  
Tung-Kuang Wu

Wireless charging technology has been developing rapidly in recent years and has been used to deliver power and provide a new source of energy for wireless rechargeable sensor networks. With current solutions, charging is usually done by a mobile vehicle equipped with a charger, which needs to be waiting on site until the sensor is properly charged. It is possible that some sensors drain their power while the charging vehicle is serving the other. Accordingly, we proposed a solution that uses a single charging vehicle equipped with multiple battery cells, which we call the separable charging array. The battery cell can be unloaded on site with sensor, while the vehicle carries on its mission. A scheduling algorithm, a revised earliest deadline first algorithm, is proposed to work with this new model. In this study, we will demonstrate that the idea of equipping charging vehicle with separable charger array is feasible. In addition, our simulations indicate that the revised earliest deadline first scheduling algorithm does improve the earliest deadline first scheduling algorithm significantly with only minor overhead in scheduling computation time and very few extra chargers. Some modified variations of the proposed revised earliest deadline first algorithm will also be discussed and evaluated.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Shujuan Huang ◽  
Tiansen Li ◽  
Zhihao Ma ◽  
Feng Xiao ◽  
Wenjuan Zhang

Most of the multiprocessor real-time scheduling algorithms follow the partitioned approach, the global approach, or the semipartitioned approach which is a hybrid of the first two by allowing a small subset of tasks to migrate. EDF-fm (Earliest Deadline First-based Fixed and Migrating) and EDF-os (Earliest Deadline First-based Optimal Semipartitioned) are semipartitioned approaches and were proposed for soft real-time sporadic task systems. Despite their desirable property that migrations are boundary-limited such as they can only occur at job boundaries, EDF-fm and EDF-os are not always optimal and have higher tardiness and cost of overheads due to task migration. To address these issues, in this paper, we classify the systems into different types according to the utilization of their tasks and propose a new semipartitioned scheduling algorithm, earliest deadline first-adaptive, dubbed as EDF-adaptive. Our experiments show that EDF-adaptive can achieve better performance than EDF-fm and EDF-os, in terms of system utilization and tardiness overhead. It is also proved that EDF-adaptive is able to lessen the task migration overhead, by reducing the number of migrating jobs and the number of processors to which a task is migrated.


2012 ◽  
Vol 501 ◽  
pp. 151-155
Author(s):  
Yong Liu ◽  
Ge Zhang ◽  
Hua Yan ◽  
Yu Mei Ding ◽  
Wei Min Yang

In this article, three kinds of belt named B, C and D type are invented, then their main performance are compared with the other two kinds of belt structures introduced in previous papers. Simulation results showed that B and D-type belts are better than the other three. Comparatively the latter needs less material, its molding process is easier, and the tire body is lighter than B type tire, so in general it can be considered that D-type belt is the best among the five kinds of belt structures.


2014 ◽  
Vol 631-632 ◽  
pp. 761-765
Author(s):  
Jing Cun Bi ◽  
Qi Li ◽  
Wei Jun Yang ◽  
Yan Fei Liu

As for the aperiodic tasks of node in network control systems, the FC-ABS (Feedback Controlled Adaptive Bandwidth Server) scheduling algorithm is designed. The different scheduling methods are used according to time characteristics of aperiodic tasks, and feedback scheduling is used to mitigate the effect of aperiodic tasks on periodic tasks. The simulation results show that the method is effective. Keyword: Network Control Systems; Server Scheduling; Feedback Scheduling; FC-ABS.


Author(s):  
Apurva Shah ◽  
Ketan Kotecha

The Ant Colony Optimization (ACO) algorithms are computational models inspired by the collective foraging behavior of ants. The ACO algorithms provide inherent parallelism, which is very useful in multiprocessor environments. They provide balance between exploration and exploitation along with robustness and simplicity of individual agent. In this paper, ACO based dynamic scheduling algorithm for homogeneous multiprocessor real-time systems is proposed. The results obtained during simulation are measured in terms of Success Ratio (SR) and Effective CPU Utilization (ECU) and compared with the results of Earliest Deadline First (EDF) algorithm in the same environment. It has been observed that the proposed algorithm is very efficient in underloaded conditions and it performs very well during overloaded conditions also. Moreover, the proposed algorithm can schedule some typical instances successfully which are not possible to schedule using EDF algorithm.


2012 ◽  
Vol 268-270 ◽  
pp. 1426-1431
Author(s):  
Jian Jun Yi ◽  
Fei Luo ◽  
Shao Li Chen ◽  
Bai Yang Ji ◽  
Hai Xu Yan

RFID anti-collision technology is one of a key technology in RFID application system. Anti-collision algorithms for RFID systems include tag anti-collision algorithms and reader anti-collision algorithms. This paper focused on the impoved binary algorithm and dynamic binary algorithm. An improved algorithm has been proposed, in which the collision bits was put into the stack and they were used as the reader’s request. Based on this mechanism, a novel binary stack algorithm has been proposed. Its simulation was given to analyze the performance of this algorithm. The simulation results showed that the amount of transmitted data in proposed algorithm was obviously less than those in the other two traditional algorithms with the number of tags and their bytes increasing. Consequently, the performance of the proposed algorithm is much better than that of the traditional anti-collision binary algorithm.


Scheduling transmissions in a well-organized and fair manner in multi hop wireless network [MWN] is very crucial and challenging .For semi equalizing the load a distributed node scheduling algorithm is used through slot reallocation based on local information swap . The algorithm helps to find the delay or shortest delivery time is achieved when the load is semi-equalized throughout the network. We have simulated the Local voting algorithm and found that the system converges asymptotically toward the optimal schedule. In this paper we propose a congestion free scheme to schedule the node transmissions conflict free. The proposed algorithm achieves better performance than the other distributed algorithms in terms of fairness, average delay, and maximum delay in simulation results.


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