Feedback-control & queueing theory-based resource management for streaming applications

Recent advances in sensor technologies and instrumentation have led to an extraordinary growth of data sources and streaming applications. A wide variety of devices, from smart phones to dedicated sensors, have the capability of collecting and streaming large amounts of data at unprecedented rates. A number of distinct streaming data models have been proposed. Typical applications for this include smart cites & built environments for instance, where sensor-based infrastructures continue to increase in scale and variety. Understanding how such streaming content can be processed within some time threshold remains a non-trivial and important research topic. We investigate how a cloud-based computational infrastructure can autonomically respond to such streaming content, offering Quality of Service guarantees. We propose an autonomic controller (based on feedback control and queueing theory) to elastically provision virtual machines to meet performance targets associated with a particular data stream. Evaluation is carried out using a federated Cloud-based infrastructure (implemented using CometCloud) – where the allocation of new resources can be based on: (i) differences between sites, i.e. types of resources supported (e.g. GPU vs. CPU only), (ii) cost of execution; (iii) failure rate and likely resilience, etc. In particular, we demonstrate how Little’s Law –a widely used result in queuing theory– can be adapted to support dynamic control in the context of such resource provisioning

Mobility-aware application scheduling in fog computing

Fog computing provides a distributed infrastructure at the edges of the network, resulting in low-latency access and faster response to application requests when compared to centralized clouds. With this new level of computing capacity introduced between users and the data center-based clouds, new forms of resource allocation and management can be developed to take advantage of the Fog infrastructure. A wide range of applications with different requirements run on end-user devices, and with the popularity of cloud computing many of them rely on remote processing or storage. As clouds are primarily delivered through centralized data centers, such remote processing/storage usually takes place at a single location that hosts user applications and data. The distributed capacity provided by Fog computing allows execution and storage to be performed at different locations. The combination of distributed capacity, the range and types of user applications, and the mobility of smart devices require resource management and scheduling strategies that takes into account these factors altogether. We analyze the scheduling problem in Fog computing, focusing on how user mobility can influence application performance and how three different scheduling policies, namely concurrent, FCFS, and delay-priority, can be used to improve execution based on application characteristics

Federated Computing for the Masses – Aggregating Resources to Tackle Large-scale Engineering Problems

The complexity of many problems in science and engineering requires computational capacity exceeding what average user can expect from a single computational center. While many of these problems can be viewed as a set of independent tasks, their collective complexity easily requires millions core-hours on any state-of-the-art HPC resource, and throughput that cannot be sustained by a single multi-user queuing system. In this paper we explore the use of aggregated HPC resources to solve large-scale engineering problems. We show it is possible to build a computational federation that is easy to use by end-users, and is elastic, resilient and scalable. We argue that the fusion of federated computing and real-life engineering problems can be brought to average user if relevant middleware is provided. We report on the use of federation of 10 distributed heterogeneous HPC resources to perform a large-scale interrogation of the parameter space in the microscale fluid flow problem

A computational model to support in-network data analysis in federated ecosystems

Software-defined networks (SDNs) have proven to be an efficacious tool for undertaking complex data analysis and manipulation within data intensive applications. SDN technology allows us to separate the data path from the control path, enabling in-network processing capabilities to be supported as data is migrated across the network. We propose to leverage software-defined networking (SDN) to gain control over the data transport service with the purpose of dynamically establishing data routes such that we can opportunistically exploit the latent computational capabilities located along the network path. This strategy allows us to minimize waiting times at the destination data center and to cope with spikes in demand for computational capability. We validate our approach using a smart building application in a multi-cloud infrastructure. Results show how the in-transit processing strategy increases the computational capabilities of the infrastructure and influences the percentage of job completion without significantly impacting costs and overheads

Coordinating data analysis and management in multi-layered clouds

We introduce an architecture for undertaking data processing across multiple layers of a distributed computing infrastructure, composed of edge devices (making use of Internet-of-Things (IoT) based protocols), intermediate gateway nodes and large scale data centres. In this way, data processing that is intended to be carried out in the data centre can be pushed to the edges of the network -- enabling more efficient use of data centre and in-network resources. We suggest the need for specialist data analysis and management algorithms that are resource-aware, and are able to split computation across these different layers. We propose a coordination mechanism that is able to combine different types of data processing capability, such as in-transit and in-situ. An application scenario is used to illustrate the concepts, subsequently evaluated through a multi-site deployment

Deadline constrained video analysis via in-transit computational environments

Combining edge processing (at data capture site) with analysis carried out while data is enroute from the capture site to a data center offers a variety of different processing models. Such in-transit nodes include network data centers that have generally been used to support content distribution (providing support for data multicast and caching), but have recently started to offer user-defined programmability, through Software Defined Networks (SDN) capability, e.g. OpenFlow and Network Function Visualization (NFV). We demonstrate how this multi-site computational capability can be aggregated to support video analytics, with Quality of Service and cost constraints (e.g. latency-bound analysis). The use of SDN technology enables separation of the data path from the control path, enabling in-network processing capabilities to be supported as data is migrated across the network. We propose to leverage SDN capability to gain control over the data transport service with the purpose of dynamically establishing data routes such that we can opportunistically exploit the latent computational capabilities located along the network path. Using a number of scenarios, we demonstrate the benefits and limitations of this approach for video analysis, comparing this with the baseline scenario of undertaking all such analysis at a data center located at the core of the infrastructure.TS

Edge-supported approximate analysis for long running computations

With the increasing availability of Internet of Things (IoT) devices, and potential applications that make use of data from such devices, there is a need to better identify appropriate data processing techniques that can be applied to this data. The computational complexity of these applications, and the complexity of the requirements on the data processing techniques, often derives from the capabilities of current IoT devices and the need to integrate data streams across multiple IoT devices, which result in larger data sizes and loads on the computing infrastructure. Furthermore, due to the dynamics and uncertainties of edge environments, it is essential that these techniques are capable of adapting across a range of computational and data transfer requirements (such as execution performance) and infrastructure scales (processing nodes, storage needs, network requirements) to carry out a particular analysis task, in response to changing requirements and constraints. Approximate computing offers techniques that can simplify the overall analysis workflow, trading off loss in quality and optimality of the solution with time to reach a particular outcome. These techniques have two main advantages: (i) reduced time to execute a particular data analysis; (ii) reduced requirements on the computational infrastructure (i.e., lower energy, computational resource needs, etc) to carry out such analysis. With data processing capabilities available IoT devices and associated gateway nodes, such approximate computing can be achieved at or close to the network edge. In this paper, we propose in-transit and edge-supported approximation techniques, which can undertake partial/approximate data processing at the data generation/capture or aggregation site, prior to delivery to a cloud data center. We also demonstrate how such an approach can be used in practice by applying it to support energy optimization in built environments (utilizing a combination of sensors and cloud-based data analysis). Several approximation techniques that are relevant in this context are presented, and their relevance explored and evaluated in the context of an energy simulation application scenario

Coordinating data analysis and management in multi-layered clouds

We introduce an architecture for undertaking data processing across multiple layers of a distributed computing infrastructure, composed of edge devices (making use of Internet-of-Things (IoT) based protocols), intermediate gateway nodes and large scale data centres. In this way, data processing that is intended to be carried out in the data centre can be pushed to the edges of the network -- enabling more efficient use of data centre and in-network resources. We suggest the need for specialist data analysis and management algorithms that are resource-aware, and are able to split computation across these different layers. We propose a coordination mechanism that is able to combine different types of data processing capability, such as in-transit and in-situ. An application scenario is used to illustrate the concepts, subsequently evaluated through a multi-site deployment

Computational resource management for data-driven applications with deadline constraints

Recent advances in the type and variety of sensing technologies have led to an extraordinary growth in the volume of data being produced and led to a number of streaming applications that make use of this data. Sensors typically monitor environmental or physical phenomenon at predefined time intervals or triggered by user-defined events. Understanding how such streaming content (the raw data or events) can be processed within a time threshold remains an important research challenge. We investigate how a cloud-based computational infrastructure can autonomically respond to such streaming content, offering quality of service guarantees. In particular, we contextualize our approach using an electric vehicles (EVs) charging scenario, where such vehicles need to connect to the electrical grid to charge their batteries. There has been an emerging interest in EV aggregators (primarily intermediate brokers able to estimate aggregate charging demand for a collection of EVs) to coordinate the charging process. We consider predicting EV charging demand as a potential workload with execution time constraints. We assume that an EV aggregator manages a number of geographic areas and a pool of computational resources of a cloud computing cluster to support scheduling of EV charging. The objective is to ensure that there is enough computational capacity to satisfy the requirements for managing EV battery charging requests within specific time constraints