Multi-tree genetic programming for adaptive dynamic fault-tolerant task scheduling of satellite edge computing

<span>The distributed fog node network and variable workloads make task distribution difficult in fog computing. Optimizing computing resources for dynamic workloads with heuristic and metaheuristic algorithms has shown potential. To address changing workloads, these algorithms enable real-time decision-making. This systematic review examines heuristic, meta-heuristic, and real-time dynamic job scheduling strategies in fog computing. Static methods like heuristic and meta-heuristic algorithms can help modify dynamic task scheduling in fog computing situations. This paper covers a current study area that stresses real-time approaches, meta-heuristics, and fog computing environments' dynamic nature. It also helps build reliable and scalable fog computing systems by spotting dynamic task scheduling trends, patterns, and issues. This study summarizes and analyzes the latest fog computing research on task-scheduling algorithms and their pros and cons to adequately address their issues. Fog computing task scheduling strategies are detailed and classified using a technical taxonomy. This work promises to improve system performance, resource utilization, and fog computing settings. The work also identifies fog computing job scheduling innovations and improvements. It reveals the strengths and weaknesses of present techniques, paving the way for fog computing research to address unresolved difficulties and anticipate future challenges.</span>

Heterogeneous systems with multiple different compute devices have come into common use recently, and the heterogeneity of the compute device is mainly reflected in three aspects: hardware architecture, instruction set architecture, and processing capability. Heterogeneous CPU-accelerator systems have attracted increasing attention especially. To make full use of multiple CPUs and accelerators to execute data-parallel applications, programmers may need to manually map computation and data to all available compute devices, which is tedious, error-prone, and difficult. Especially for some data-parallel applications, the inter-device communication could easily become the performance bottleneck of multi-device co-execution. Therefore, firstly, a runtime system is designed for supporting heterogeneous cooperative execution (HCE) of data-parallel applications, which can help programmers to automatically and efficiently map computation and data to multiple compute devices. Secondly, an incremental data transfer method is designed to avoid redundant data transfers between devices, and a three-way overlapping communication optimization method based on software pipelining is designed to effectively hide the inter-device communication overhead. Based on our previously proposed feedback-based dynamic and elastic task scheduling (FDETS) scheme and asynchronous-based dynamic and elastic task scheduling (ADETS) scheme, the modified FDETS that supports incremental data transfer and the modified ADETS that supports three-way overlapping communication optimization are proposed, which not only can effectively partition and balance the workload among multiple compute devices but also can significantly reduce data transfer overhead between devices. Thirdly, a prototype of the proposed runtime system is implemented, which provides a set of runtime APIs for task scheduling, device management, memory management, and transfer optimization. Our experimental results show that the communication overhead between devices is greatly reduced using the proposed inter-device communication optimization methods and the multi-device co-execution significantly outperforms the best single-device execution.

Multitasking learning has been successfully used in handling multiple related tasks simultaneously. In reality, there are often many tasks to be solved together, and the relatedness between them is unknown in advance. In this paper, we focus on multitask genetic programming for the dynamic flexible job shop scheduling problems, and address two challenges. The first is how to measure the relatedness between tasks accurately. The second is how to select task pairs to transfer knowledge during the multitask learning process. To measure the relatedness between dynamic flexible job shop scheduling tasks, we propose a new relatedness metric based on the behaviour distributions of the variable-length genetic programming individuals. In addition, for more effective knowledge transfer, we develop an adaptive strategy to choose the most suitable assisted task for the target task based on the relatedness information between tasks. The findings show that in all of the multitask scenarios studied, the proposed algorithm can substantially increase the effectiveness of the learned scheduling heuristics for all the desired tasks. The effectiveness of the proposed algorithm has also been verified by the analyses of task relatedness and structures of the evolved scheduling heuristics, and the discussions of population diversity and knowledge transfer.

In recent years, high-definition (HD) maps are considered to be significant complements to the on-board sensors of autonomous vehicles. Due to the highly dynamic characteristic of HD map, how to update HD maps fast and efficiently has become the pivotal issue which attracts great attentions. Currently, most of the research on this issue focuses on the crowdsourcing protocol design or specific updating method meanwhile disregarding the need of communication and computing resource in HD map update. Therefore, in this paper, we propose an integrated update framework including both an adaptive data transmission scheme and an adaptive task scheduling scheme to realize fast data collection and fast data processing for HD map update. To the best of our knowledge, this is the first work that addresses the problem of HD map update which takes the need of communication and computing resource into consideration. In this paper, we firstly illustrate the system architecture of our HD map update framework. Based on that, to realize fast data collection, we propose an adaptive data transmission scheme, which optimizes the transmission rate on different links of each vehicle considering the wireless channel capacity and fronthaul link capacity of the access points. Besides, to realize fast data processing, we propose an adaptive task scheduling scheme, which enables cooperative computing between the edge nodes and cloud computing server, considering the constraints of computing capacity and backhaul link capacity. To the end, we carry out simulations to verify the effectiveness of our proposed policies.

Efficient dynamic task scheduling in virtualized data centers with fuzzy prediction

Distributed computing engines, such as Spark, are widely used to process the large volumes of data collected by the Internet of Things (IoT) devices. In IoT systems, computing nodes often exhibit significant heterogeneity. However, most existing task scheduling algorithms neglect the performance differences among system nodes and statically assign tasks based on data locality. When high-performance nodes complete local tasks rapidly, they are subsequently assigned massive non-local tasks, resulting in severe network congestion and performance degradation. To address these issues, we propose a dynamic resource utilization-aware task scheduling strategy (DRUTS), which can efficiently utilize idle bandwidth and high-performance computing resources while also ensuring data locality. Firstly, considering the time-varying characteristics of heterogeneous node performance under various workloads, we use a sliding window to process the task information stream and evaluate the relative performance of nodes in real-time. Then, our proposed strategy adopts weighted random methods to dynamically select task <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">providers</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">receivers</i> by combining the cluster network load. Finally, it migrates and pre-executes tasks to high-performance nodes based on data distribution. We evaluate our proposed strategy performance using six typical workloads on two types of real-world heterogeneous clusters. The experimental results clearly demonstrate that our proposed strategy not only improves CPU and network utilization by 15.7% and 13.2%, respectively, but also reduces application execution time by 37.2% compared to existing work.

This book has addressed several issues in multiprocessor architectures and parallel algorithms for Integrated Vision Systems. The approach has been to consider computational requirements for vision applications in an integrated environment in designing a multiprocessor architecture rather than to propose architecture solutions to perform individual algorithms efficiently. An IVS involves algorithms from several levels of processing and the characteristics of algorithms in each level differ tremendously from algorithms in other levels. However, these algorithms need to exist in a system simultaneously and interact with each other. Therefore, a multiprocessor architecture suitable for IVS applications must be partitionable and reconfigurable. It must have the capability to allocate resources dynamically, provide for dynamic load balancing and task scheduling, provide fast and flexible communication, provide efficient I/O, and be fault-tolerant, in addition to providing raw processing power.

A variety of novel mobile applications are developed to attract the interests of potential users in the emerging 5G-enabled vehicular networks. Although computation offloading and task scheduling have been widely investigated, it is rather challenging to decide the optimal offloading ratio and perform adaptive task scheduling in high-dynamic networks. Furthermore, the scheduling policy made by the network operator may be violated, since vehicular users are rational and selfish to maximize their own profits. By considering the incentive compatibility and individual rationality of vehicular users, we present POETS, an efficient partial computation offloading and adaptive task scheduling algorithm to maximize the overall system-wide profit. Specially, a two-sided matching algorithm is first proposed to derive the optimal transmission scheduling discipline. After that, the offloading ratio of vehicular users can be obtained through convex optimization, without any information of other users. Furthermore, a non-cooperative game is constructed to derive the payoff of vehicular users that can reach the equilibrium between users and the network operator. Theoretical analyses and performance evaluations based on real-world traces of taxies demonstrate the effectiveness of our proposed solution.

Cloud computing enables the internet based computing to everywhere. In cloud computing the task scheduling and load balancing is the important issue that must be considered in data centers. In cloud platform service providers allocate the resources based on the available resources this will increase the QoS. The process of distributing workloads is a load balancing Technique. In this paper focusing the load balancing between the virtual machine. Load balancing are different types that is network load, memory capacity, storage capacity and CPU load. Load balancing supports failover, enabling scalability and decreases costs and maximizes the resource availability. This paper presents the detailed review of load balancing with machine learning technique such as naïve bayes, random forest, Decision Tree and Support Vector Machine. By these machine learning model, SVM algorithm significantly to classify the incoming request to reduce the processing time (makespan). Also provide the moth flame optimization technique for dynamic task scheduling to make better scheduling under different load condition. We have experimented and evaluated this algorithm in a cloud simulation environment; we obtain better outcome than some other well-known algorithms. The Simulation results demonstrate that the proposed technique has a better development in terms of reducing the makespan time and load balancing.

The scheduling of tasks with deadlines on clusters is a key issue for offering quality-of-service (QoS) assurance. A critical challenge in real-time task scheduling is to handle various types of applications. This paper investigates the scheduling problem for processing a set of tasks comprising both divisible and indivisible real-time tasks on cluster systems. Indivisible tasks are characterized by the property that they need to be processed on their entirety on a single processor while divisible tasks can be distributed across several processing nodes by exploiting the underlying data parallelism. We propose a dynamic (on-line) real-time scheduling algorithm referred to as Hybrid Loads Push-Pull Scheduling (HLPPS) algorithm for handling a set of tasks comprising both divisible and indivisible real-time tasks on cluster systems. HLPPS is shown to efficiently exploit the parallelism in divisible tasks without undermining the schedulability of indivisible tasks and thereby optimize the overall performance. We consider two distinct network platforms - tightly coupled and loosely coupled clusters in designing the strategy. We conduct extensive performance evaluation studies to quantify the performance of the proposed algorithm under a variety of scenarios.

Recommendation systems typically rely on users’ historical behavior to infer their preferences. However, when new entries emerge, the system cannot make accurate prediction due to the lack of historical data. This is known as the “cold-start” problem, which not only limits the exposure of new items but also impacts the first experience of new users severely. Meta-learning has emerged as a promising approach to address this issue, but existing methods have limitations in dealing with the differences in user preferences and sparse monitoring data. To overcome these limitations, Dual enhanced Meta-learning with Adaptive Task Sampling is proposed. First, we propose an embedding enhancement strategy for cold nodes. Specifically, we map the cold-start embeddings into the warm space based on the common features shared across all nodes, and then add uniform noise to create the contrastive views. This strategy injects warm co-occurrence signals into the content of cold nodes, effectively enriching the feature space of cold nodes. Second, we introduce an adaptive task scheduler to measure the effectiveness of different meta-tasks and filter out the noise from invalid tasks. We assign different sampling probabilities to the tasks based on the learning process (gradient similarity) and the learning result (loss) of the meta-tasks. Finally, we consider the above two modules as auxiliary tasks for the main meta-model. Then, joint optimization is carried out through a multi-task learning framework. Experiments in three cold-start scenarios show that our approach outperforms the most advanced baselines, including traditional methods, HIN-based methods, and meta-learning-based methods.

We introduce a new set of dynamic scheduling algorithms for scheduling and guaranteeing the deadline compliance of a set of aperiodic real-time tasks on a uniprocessor architecture. The task model selected is that of non-preemptable tasks with arbitrary start times and deadlines. The proposed algorithms address a fundamental trade-off in dynamic scheduling between the cost of scheduling and the quality of the resulting schedules. The algorithms control the time allocated to scheduling explicitly, in order to obtain good-quality schedules in reasonable times. We show that taking into account the scheduling time is crucial for honoring the deadlines of scheduled real-time tasks. We provide an experimental evaluation of our algorithms via performance comparisons with existing landmark algorithms that were originally designed to address some similar issues. The results of our experiments show that our algorithms outperform the existing techniques in several parameter configurations.

Genetic programming has been explored in recent works to evolve hyper-heuristics for dynamic flexible job shop scheduling. To generate optimum rules, the algorithm searches a space of trees composed from a set of terminals and operators. Since the search space is exponentially proportional to the size of the terminal set, it is preferred to opt out any insignificant terminals. Feature selection techniques has been employed to reduce the terminal set size without discarding any important information and they have proven to be effective for enhancing search performance and efficiency for dynamic flexible job shop scheduling. In this paper, we extends our previous work by adding a modified version of the two-stage genetic programming algorithm and by comparing the different methods in a larger experimental setup. The results show that feature selection can generate better rules in most of the cases while also being more efficient to in a production environment.KeywordsFeature selectionFlexible job shop schedulingDynamic schedulingGenetic programmingHyper heuristics

This paper analyzes the impact of dynamic task scheduling, processing element allocation and data transfer management on system performance of heterogeneous MPSoCs. Therefore, all parts of a runtime scheduling unit are analyzed. Bottlenecks are identified and their complexity evaluated. Furthermore, traced information is processed with two newly introduced tools. The first one generates an annotated SDF3 file. The second one creates a static schedule which applies the same scheduling and allocation decision as the dynamic scheduler. The execution of the static schedule reduces the burden of task management to a minimum. The resulting static execution is compared with the execution of the dynamic schedule. Hence, runtime overhead of dynamic scheduling is unveiled.

Edge Cloud (EC) is poised to brace massive machine type communication (mMTC) for 5G and IoT by providing compute and network resources at the edge. Yet, the EC being regionally domestic with a smaller scale, faces the challenges of bandwidth and computational throughput. Resource management techniques are considered necessary to achieve efficient resource allocation objectives. Software Defined Network (SDN) enabled EC architecture is emerging as a potential solution that enables dynamic bandwidth allocation and task scheduling for latency sensitive and diverse mobile applications in the EC environment. This study proposes a novel Heuristic Reinforcement Learning (HRL) based flow-level dynamic bandwidth allocation framework and validates it through end-to-end implementation using OpenFlow meter feature. OpenFlow meter provides granular control and allows demand-based flow management to meet the diverse QoS requirements germane to IoT traffics. The proposed framework is then evaluated by emulating an EC scenario based on real NSF COSMOS testbed topology at The City College of New York. A specific heuristic reinforcement learning with linear-annealing technique and a pruning principle are proposed and compared with the baseline approach. Our proposed strategy performs consistently in both Mininet and hardware OpenFlow switches based environments. The performance evaluation considers key metrics associated with real-time applications: throughput, end-to-end delay, packet loss rate, and overall system cost for bandwidth allocation. Furthermore, our proposed linear annealing method achieves faster convergence rate and better reward in terms of system cost, and the proposed pruning principle remarkably reduces control traffic in the network.