The increasing complexity of distributed computing environments necessitates efficient resource management strategies to optimize performance and minimize resource consumption. Although proactive horizontal autoscaling dynamically adjusts computational resources based on workload predictions, existing approaches primarily focus on improving workload resource consumption, often neglecting the overhead introduced by the autoscaling system itself. This could have dire ramifications on resource efficiency, since many prior solutions rely on multiple forecasting models per compute node or group of pods, leading to significant resource consumption associated with the autoscaling system. To address this, we propose GraphOpticon, a novel proactive horizontal autoscaling framework that leverages a singular global forecasting model based on Spatiotemporal Graph Neural Networks. The experimental results demonstrate that GraphOpticon is capable of providing improved service performance, and resource consumption (caused by the workloads involved and the autoscaling system itself). As a matter of fact, GraphOpticon manages to consistently outperform other contemporary horizontal autoscaling solutions, such as Kubernetes’ Horizontal Pod Autoscaler, with improvements of 6.62% in median execution time, 7.62% in tail latency, and 6.77% in resource consumption, among others.

Continuous Integration/Deployment (CI/CD) pipelines are critical for integrating developer changes and maintaining high-quality software deployments. The increasing frequency of commits and deployments places significant demands on CI/CD systems, requiring improved speed and efficiency. While numerous tools and techniques have been proposed to increase the velocity of CI/CD pipelines, there is a notable gap in architectural guidance for developers on key design decisions and best practices. To address this, we conducted a grey literature review using Straussian Grounded Theory to develop a UML-based model to guide software architects and developers in their decision-making. Our research focuses on identifying architectural design decisions (ADDs) and best practices as decision options that improve the speed and efficiency of CI/CD pipelines. The study analyses 38 sources, building a formal model comprising 6 ADDs and 30 best practices. This work contributes a structured, architecturally guided approach to optimizing CI/CD systems.

This paper presents a novel algorithm for the Vertex Cover problem, inspired by the Think-Like-A-Vertex (TLAV) paradigm. The Vertex Cover problem, a fundamental challenge in graph theory, finds significant relevance in the context of the compute continuum, where the optimal placement of application images across a diverse range of computational resources is a critical concern. Our proposed TLAV-based algorithm addresses this challenge by leveraging local information at each vertex to make intelligent decisions, thereby reducing the global complexity of the problem. While this approach could potentially lead to resource overprovisioning, we argue that in the context of the compute continuum, this trade-off can provide more flexibility and redundancy, enhancing the reliability of the system. Through extensive analysis and experimental results, we demonstrate the efficiency and scalability of our algorithm on large-scale graphs, making a significant contribution to the field of resource management in the compute continuum.

Edge computing presents a promising paradigm for the management and processing of the vast volumes of data generated by Internet of Things (IoT) devices. By merging cloud services with decentralized processing at the edge of the network, edge computing optimizes resource utilization while mitigating communication overhead and data transfer delays. Despite advancements, there are issues regarding cloud/edge-based application requirements. A distributed edge storage solution is crucial, ensuring data proximity, minimizing network congestion, and adapting to changing demands. Nevertheless, implementing or selecting an efficient edge-enabled storage system presents numerous challenges due to the distributed and heterogeneous nature of the edge, as well as its limited resource capabilities. Hence, it is essential for the research community to actively contribute towards clarifying the objectives and delineating the strengths and weaknesses of different storage solutions. This work presents an overview and performance analysis of three storage solutions in the edge computing context, namely MinIO, IPFS, and BigchainDB. The evaluation considers a set of Quality of Service (QoS) and resource utilization metrics. The systems are deployed on a cluster of four Raspberry Pis, which function as a network of edge devices. The results demonstrate the superiority of IPFS and provide insights into the performance of the evaluated storage systems for edge deployments.

In this paper we examine different approaches for the prediction of Service Level Agreements (SLAs) violations that occur during the service provisioning between cloud customers and providers. Despite the fact that there are many network metrics that involve the server - client interaction, it is an open research question how these available metrics can be used by a SLA prediction mechanism. We study three different data representation models for the network characteristics, a time series, a content and a context representation. We see that a context approach using graph representations captures efficiently the associativity of clients and improves the performance of traditional SLA violation prediction models when it is combined with them. The prediction of the SLA violations takes place using neural networks, making us propose a composite SLA prediction model that leverages Graph Neural Networks (GNNs). In our research, we put special emphasis and try different variations on how we construct the graphs. We perform an extensive performance evaluation of 23 different SLA prediction models that can be grouped into the three representations categories, namely the vector models that are based on network features, sequential models that leverage the temporal evolution of QoS metrics and Graph models that take into consideration the associativity of the clients. The experimental results show that our proposed GNN-based model can significantly improve the accuracy of SLA violation prediction, making it a useful tool for Cloud and Service providers.

The transition from Cloud Computing to a Cloud-Edge continuum brings many new exciting possibilities for interactive and data-intensive Next Generation applications, but as many challenges. Approaches and solutions that successfully worked in the Cloud space now need to be rethought for the Edge's distributed, heterogeneous and dynamic ecosystem. The placement of application images needs to be proactively devised to reduce as much as possible the image transfer time and comply with the dynamic nature and strict requirements of the applications. To this end, this paper proposes an approach based on the combination of Graph Neural Networks and actor-critic Reinforcement Learning. The approach is analyzed empirically and compared with a state-of-the-art solution. The results show that the proposed approach exhibits a larger execution times but generally better results in terms of application image placement.

Emerging cross-reality (XR) applications, including holography, augmented, virtual, and mixed reality, are characterized by unprecedented requirements for Quality of Experience (QoE), largely exceeding those currently attainable. To cope with these requirements, noticeable efforts and a number of initiatives are ongoing to enhance the current communications technologies, especially in the direction of supporting ultralow latency and increased bandwidth. This work proposes an architecture that puts together the key enablers to support future XR applications, highlighting the shortcomings of existing technologies and leveraging the ongoing innovations. It demonstrates the feasibility of the proposed architecture by describing the processes driving the platform with relevant use case scenarios, and mapping the envisioned functionality to existing tools.

The proliferation of Internet of Things (IoT) and edge devices constitute important an efficient orchestration of the edge computing infrastructures, calling the providers to rethink their decision making methods. The resource usage prediction can be a prominent source of information for adaptive resource allocation and task offloading. In this research, we propose a Gated Recurrent Neural Network multi-output regression model that leverage time series resource usage metrics. The edge computing infrastructures are characterized as dynamical and heterogeneous environments. This motivated us to propose the innovative Hybrid Bayesian Evolutionary Strategy (HBES) algorithm for automated adaptation of the resource usage models in order to to enhance the generality of our approach. The proposed resource usage prediction mechanism has been experimentally evaluated and compared with other state of the art methods with significant improvements in terms of RMSE and MAE.

This paper presents a centralized algorithm that targets at balancing energy supply to demand by controlling the charging power of EVs. Such a capability enables demand side management and facilitates a smoother integration of charging infrastructure to the grid. The algorithm targets charging management systems that handle multiple concurrent sessions in a deterministic manner It enables the creation of custom charging profiles according to user or system defined strategies and encompasses a mechanism that enables priotirization. The algorithm is designed to target the static charging case. However recommendations regarding the adaptations required to target the dynamic wireless charging case are reported.