Valgreen: an Application's Energy Profiler

International audienceThe popularity of hand-held and portable devices put the energy aware computing in evidence. The need for long time batteries surpasses the hardware manufacturer, impacting the operational system policies and software development. Power modeling of applications has been studied during the last years and can be used to estimate their total energy. In order to aid the programmer to implement energy efficient algorithms, this paper introduces an application's energy profiler, namely Valgreen, which exploits the battery's information in order to generate an architecture independent power model through a calibration process

Energy Consumption Library

International audienceThe energy consumption of a computing system depends not only on its architecture, but also on its usage. This paper describes the Energy Consumption Library (libec), a modular library of sensors and power estimators, which do not depend on wattmeter to measure the power dissipated by a machine and/or the applications that it executes, etc. In addition, four use cases are used to demonstrate some of the library's capabilities

e-Flooding: Crisis Management through Two Temporal Loops

Floods, particularly fast ones, are recurrent natural disasters with a large impact on people and infrastructures. In order to mitigate their impact most countries created regulatory frameworks to coordinate the large number of actors participating to the response of these crises. Several levels from rescue to infrastructure restoration are involved. This article proposes to improve the management of risk and resilience in areas subject to flash floods. The innovative autonomic approach presented in this article is twofold: A short-term feedback loop using a large range of information to help managing the current flood; A long-term feedback loop aiming at improving the resilience of the area to reduce the impact of future crises. The originality of these two loops consists in their link which helps improving the quality of both by feeding each other. This article also describes a scenario showing several benefits of the proposed approach

Heuristiques d'ordonnancement pour les centres de données alimentés par énergies renouvelables

International audienceLa consommation d'énergie des centres de données est un sujet qui est devenu, au cours des dernières années, de plus en plus important. L'utilisation de sources d'énergies renouvelables pour alimenter ces derniers est une perspective intéressante pour réduire, à terme, leur coût d'exploitation et leur impact écologique. Cependant, la nature intermittente des principales énergies renouvelables pose de nouveaux problèmes. Dans cet article, nous proposons une approche d'ordonnancement de tâches prenant en compte la disponibilité des énergies renouvelables pour maximiser leur utilisation. Nous avons implémenté cette approche dans un simulateur de centre de données et l'avons évaluée en considérant un centre alimenté par des panneaux photovoltaïques et connecté au réseau électrique. Les résultats indiquent une réduction de la consommation d'énergie non renouvelable jusqu'à 49% comparé à un ordonnancement classique ne prenant pas en compte la disponibilité de l'énergie renouvelable

Réduction de la consommation énergétique dans les centres de serveurs

National audienceCet article traite de la réduction d'énergie dans les systèmes à large échelle, plus particulièrement l'impact de la prise en compte de la consommation énergétique sur la consolidation de serveurs. Diminuer le nombre de machines physiques utilisées tout en garantissant une certaine qualité de services est au coeur de notre approche. Nous introduisons une métrique appelée le yield énergétique qui représente la qualité du placement de tâches sur un ensemble de machines, en prenant en compte l'économie d'énergie et la qualité de services. Elle est matérialisée par la différence entre ce qui est demandé par une tâche et ce que le système lui alloue in fine en prenant aussi en compte le facteur économie d'énergie. Nous cherchons bien entendu à minimiser cette différence. Nous proposons des heuristiques de placement que nous comparons avec l'existant et avec l'optimal. Nous présentons dans cet article un ensemble d'expérimentations qui montrent la pertinence de cette métrique pour réduire de manière significative la consommation énergétique

Energy-Aware Resource Allocation

International audienceThis paper deals with the reduction of energy consumption in large scale systems, especially by taking into account the impact of energy consumption for server consolidation. Decreasing the number of physical hosts used while ensuring a certain level of quality of services is the goal of our approach. We introduce a metric called energetic yield which represents the quality of a task placement on a subset of machines, while taking into account quality of service and energy efficiency aspects. It measures the difference between resources required by a job and what the system allocates ultimately, while trying to save energy. Our work aims at minimizing this difference. We propose placement heuristics that are compared to the optimal solution and to a related system. In this paper, we present a set of experiments showing the relevance of this metric in order to reduce significantly energy consumption

Autonomic Energy Management in a Replicated Server System

ICAS 1: AUTONOMICInternational audienceNowadays, medium or large-scale distributed infrastructures such as clusters and grids are widely used to host various kinds of applications (e.g. web servers or scientific applications). Resource management is a major challenge for most organizations that run these infrastructures. Many studies show that clusters are not used at their full capacity and that there are therefore a huge source of waste. Autonomic management systems have been introduced in order to dynamically adapt software infrastructures according to runtime conditions. They provide support to deploy, configure, monitor, and repair applications in such environments. In this paper, we report our experiments in using an autonomic management system to provide resource aware management for a clustered application. We consider a standard replicated server infrastructure in which we dynamically adapt the degree of replication in order to ensure a given response time while minimizing energy consumption

Utilization of Polyurethane Foam Dust in Development of Thermal Insulation Composite

The massive production of Polyurethane foam from various products generates an extensive amount of waste, mostly in the form of dust that is emitted while cutting, trimming, or grinding the foam. In this research, the polyurethane dust (PUD) waste is incorporated into unsaturated polyester resin (UPR) to fabricate a heat insulation composite material to be used in construction. Filler percentages ranging from 10% to 50% were used to make the UPR-PUD composite materials. The thermal and mechanical properties of the material were studied in order to evaluate the ability of the composites for this type of application. Thermogravimetric Analysis and Differential Scanning Calorimeter tests were applied to determine the thermal stability of the material. In addition, the microstructure of the prepared composites and the incorporation of PUD filler into the polyester matrix were investigated by Scanning Electron Microscopy, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) analysis. The FTIR and XRD analyses suggested that adding PUD improved the curing process of unsaturated polyester and enhanced its crystalline structure. The experimental results showed promising thermal insulation capability, with low thermal conductivity in the range of 0.076 to 0.10 W/m·K and low water retention. Moreover, the composites exhibited compression strength between 56 and 100 MPa and tensile strength between 10.3 and 28 MPa, much higher than traditional thermal insulators and many building materials

Multi-Facet Approach to Reduce Energy Consumption in Clouds and Grids: The GREEN-NET Framework

International audienceThis paper presents an integrated framework for energy savings in large scale distributed systems such as grids and clouds. The framework comprises tools and mechanisms: to measure and log data about the energy consumed by resources; to present this information to users; to involve the users in decisions to reduce the energy consumed by their applications; and to enforce energy reduction decisions automatically while respecting the users' requirements and achieving the resource availability demanded by current services. Experiments demonstrate the energy savings achieved by the proposed mechanisms and explore trade-offs between energy efficiency and performance degradation

DATAZERO: DATAcenter with Zero Emission and RObust management using renewable energy

International audienceAs the need for cloud services has been growing steadily, the size and energy consumption of datacenters have increased significantly over the past years. Due to economic and environmental constraints, energy efficiency in datacenters and greenhouse emissions have become a major concern. Renewable energy is widely seen as a promising solution to supply datacenters using local energy, without greenhouse gas emissions. However, intermittent power generation resulting from the use of renewable energy imposes a paradigm change in the way energy and computation activities are managed. On the one hand, service placement and scheduling may be used on the IT (Information Technologies) side to adapt to the available power. On the other hand, storage units may be used to lessen power generation variations. Existing literature and actual deployment mainly design optimization algorithms including the entire system (from Cloud service to electrical management, the latter often being neglected or simplified). Conversely to these approaches, we propose a solution where each side optimizes its own objectives, both interacting through a negotiation loop process to reach a common agreement. In this paper, we present DATAZERO, a project developing this idea to ensure high availability of IT services, avoiding unnecessary redundancies, under the constraints due to the intermittent nature of electrical and Cloud services flows