How to integrate precedence constraints and shared resources in real-time scheduling

Multi-core processors have become widespread computing engines for recent embedded real-time systems. Efficient task partitioning plays a significant role in real-time computing for achieving higher performance alongside sustaining system correctness and predictability and meeting all hard deadlines. This paper deals with the problem of energy-aware static partitioning of periodic, dependent real-time tasks on a homogenous multi-core platform. Concurrent access of the tasks to shared resources by multiple tasks running on different cores induced a higher blocking time, which increases the worst-case execution time (WCET) of tasks and can cause missing the hard deadlines, consequently resulting in system failure. The proposed blocking-aware-based partitioning (BABP) algorithm aims to reduce the overall energy consumption while avoiding deadline violations. Compared to existing partitioning strategies, the proposed technique achieves more energy-saving. A series of experiments test the capabilities of the suggested algorithm compared to popular heuristics partitioning algorithms. A comparison was made between the most used bin-packing algorithms and the proposed algorithm in terms of energy consumption and system schedulability. Experimental results demonstrate that the designed algorithm outperforms the Worst Fit Decreasing (WFD), Best Fit Decreasing (BFD), and Similarity-Based Partitioning (SBP) algorithms of bin-packing algorithms, reduces the energy consumption of the overall system, and improves schedulability.

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Boosted System Performance based on Execution Time Using LiMca Scheduling Algorithm

Journal of University of Shanghai for Science and Technology ◽

10.51201/jusst/21/06449 ◽

2021 ◽

Vol 23 (06) ◽

pp. 1318-1329

Author(s):

M. Sreenath ◽

◽

Dr. P. A. Vijaya ◽

Keyword(s):

Real Time ◽

Scheduling Algorithm ◽

Scheduling Algorithms ◽

Precedence Constraints ◽

Due Dates ◽

Real Time Scheduling ◽

Computational Performance ◽

Time Scheduling ◽

The Individual ◽

Optimum Solution

The scheduling algorithms have been examined by the process of task execution in a system to achieve maximum utilization of multiprocessors. Consequently, the research attempted to propose a new real-time scheduling algorithm to support a multiprocessor platform. The proposed scheduling algorithm, List Mcnaughton’s amalgamation (LiMca) scheduling algorithm has been developed for an optimum solution with the features of List and Mcnaughton’s scheduling algorithms to overcome the individual drawbacks (pre-emption and Precedence constraints). In LiMca, Workload has been distributed to the processors in a system by sorting the tasks in decreasing order with their precedence constraints including due dates, pre-emption, and context switching. In this arena, the LiMca scheduling algorithm has been developed on a traditional avionic mission system and also simulated on a real-time application. The extensive simulations were carried out on the time optimization of resources scheduling (TORSCHE) simulation toolbox. LiMca scheduling algorithm performed superior as compared to recently reported scheduling algorithms like list, hu’s, McNaughton’s, Brucker’s, and Hodgson’s in terms of computational performance.

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A Systematic Survey of Multiprocessor Real-Time Scheduling and Synchronization Protocol

International Journal of Sensors Wireless Communications and Control ◽

10.2174/2210327912666220105141851 ◽

2022 ◽

Vol 12 ◽

Author(s):

Ajitesh Kumar

Keyword(s):

Real Time ◽

Rapid Development ◽

Research Work ◽

Resource Scheduling ◽

Multiprocessor Scheduling ◽

Shared Resources ◽

Time System ◽

Real Time System ◽

Real Time Scheduling ◽

Time Scheduling

Background: Nowadays, there is an immense increase in the demand for high power computation of real-time workloads and the trend towards multi-core and multiprocessor CPUs. The real-time system needs to be implemented upon multiprocessor platforms. Introduction: The nature of processors in an embedded real-time system is changing day by day. The two most significant challenges in a multiprocessor environment are scheduling and synchronization. The popularity of real-time multi-core systems has exploded in recent years, driving the rapid development of a variety of methods for multiprocessor scheduling of essential tasks, on the other hand, these systems have constraints when it comes to maintaining synchronization in order to access shared resources. Method: This research work presents a systematic review of different existing scheduling algorithms and synchronization protocols for shared resources in a real-time multiprocessor environment. The manuscript also presents a study based on various metrics of resource scheduling and comparison among different resource scheduling techniques. Result and Conclusion: The survey classifies open issues, key challenges, and likely useful research directions. Finally, we accept that there is still a lot of capacity in getting better resource management and further maintaining the overall quality. The paper considers such a future path of research in this field.

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