Enabling Green Energy awareness in Interactive Cloud Application

International audienceWith the proliferation of Cloud computing, data centers have to urgently face energy consumption issues. Although recent efforts such as the integration of renewable energy to data centers or energy efficient techniques in (virtual) machines contribute to the reduction of carbon footprint, creating green energy awareness around Interactive Cloud Applications by smartly using the presence of green energy has not been yet addressed. By awareness, we mean the inherited capability of Software-as-a-Service applications to dynamically adapt with the availability of green energy and to reduce energy consumption while green energy is scarce or absent. In this paper, we present two application controllers based on different metrics (e.g., availability of green energy, response time, user experience level). Based on extensive experiments with a real application benchmark and workloads in Grid'5000, results suggest that providers revenue can be increased as high as 64%, while 13% brown energy can be reduced without deprovisioning any physical or virtual resources at IaaS layer and 17 fold increment of performance can be guaranteed

High-level Language Support for the Control of Reconfigurations in Component-based Architectures

International audienceNowadays, smart home is extended beyond the house itself to encompass connected platforms on the Cloud as well as mobile personal devices. This Smart Home Extended Architecture (SHEA) helps customers to remain in touch with their home everywhere and any time. The endless increase of connected devices in the home and outside within the SHEA multiplies the deployment possibilities for any application. Therefore, SHEA should be taken from now as the actual target platform for smart home application deployment. Every home is different and applications offer different services according to customer preferences. To manage this variability, we extend the feature modeling from software product line domain with deployment constraints and we present an example of a model that could address this deployment challenge

Behavioural Model-based Control for Autonomic Software Components

International audienceAutonomic Managers (AMs) have been largely used to autonomously control reconfigurations within software compo- nents. This management is performed based on past monitoring events, configurations as well as behavioural programs defining the adaptation logics and invariant properties. The challenge here is to provide assurances on navigation through the configuration space, which requires taking decisions that involve predictions on possible futures of the system. This paper proposes the design of AMs based on logical discrete control approaches, where the use of behavioural models enriches the manager with a knowledge not only on events, states and past history, but also with possible future configurations. We define a Domain Specific Language, named Ctrl-F, which provides high-level constructs to describe behavioural programs in the context of software components. The formal definition of Ctrl-F is given by translation to Finite State Automata, which allow for the exploration of behavioural programs by verification or Discrete Controller Synthesis, automatically generating a controller enforcing correct behaviours. We implement an AM by integrating the result of Ctrl-F compilation and validate it with an adaptation scenario over Znn.com, a self-adaptive case study

Evaluation of total polyphenols content and antioxidant capacity of different commercial cocoa (theobroma cacao) powders) / Avaliação do teor de polifenóis totais e capacidade antioxidante de diferentes pós comerciais de cacau (theobroma cacao)

Polyphenols from cocoa have been demonstrated to reduce blood pressure and improve endothelial function in hypertensive individuals. However, polyphenols content in commercial cocoa products may be lost during fermentation, alkalinization, and/or roasting process, impairing its bioactivity. Therefore, the current study sought to investigate whether total polyphenols content and antioxidant capacity are preserved among commercial cocoa powders. Four best-selling 100% cocoa powder products in Brazil (Garoto®, Nestle®, Mãe Terra®, and Hershey®) and one alkalinized 100% cocoa powder product (Hershey®) were examined. The total polyphenols content was determined by using the Folin-Ciocalteu’s phenol reagent and antioxidant capacity by using 22,2’-azino-bis (3- ethylbenzothiazoline-6-sulphonic acid) (ABTS) method. No significant difference in total polyphenols and antioxidant capacity among the brand of natural powder products (Garoto®, Nestle®, Mãe Terra®, and Hershey®) was observed. However, Alkalinized cocoa powder (Hershey®) exhibited significantly lower total polyphenols content and antioxidant capacity compared to other brands of natural cocoa powder products. The current study showed that total polyphenols content and antioxidant capacity are consistent between natural cocoa powder products. However, total polyphenols content and antioxidant capacity of cocoa are reduced during the alkalinization process.  

Gestion multi autonome pour l'optimisation de la consommation énergétique sur les infrastructures en nuage

As a direct consequence of the increasing popularity of Internet and Cloud Computing services, data centers are amazingly growing and hence have to urgently face energy consumption issues. Paradoxically, Cloud Computing allows infrastructure and applications to dynamically adjust the provision of both physical resources and software services in a pay-per-use manner so as to make the infrastructure more energy efficient and applications more Quality of Service (QoS) compliant. However, optimization decisions taken in isolation at a certain level may indirectly interfere in (or even neutralize) decisions taken at another level, e.g. an application requests more resources to keep its QoS while part of the infrastructure is being shutdown for energy reasons. Hence, it becomes necessary not only to establish a synergy between cloud layers but also to make these layers flexible and sensitive enough to be able to react to runtime changes and thereby fully benefit from that synergy. This thesis proposes a self-adaptation approach that considers both application internals (architectural elasticity) and infrastructure (resource elasticity) to reduce the energy footprint in cloud infrastructures. Each application and the infrastructure are equipped with their own autonomic manager, which allows them to autonomously optimize their execution. In order to get several autonomic managers working together, we propose an autonomic model for coordination and synchronization of multiple autonomic managers. The approach is experimentally validated through two studies: a qualitative (QoS improvements and energy gains) and a quantitative one (scalability).Conséquence directe de la popularité croissante des services informatique en nuage, les centres de données se développent à une vitesse vertigineuse et doivent rapidement faire face à des problèmes de consommation d'énergie. Paradoxalement, l'informatique en nuage permet aux infrastructure et applications de s'ajuster dynamiquement afin de rendre l'infrastructure plus efficace en termes d'énergie et les applications plus conformes en termes de qualité de service (QdS). Toutefois, les décisions d'optimisation prises isolément à un certain niveau peuvent indirectement interférer avec (voire neutraliser) les décisions prises à un autre niveau, par exemple, une application demande plus de ressources pour garder sa QdS alors qu'une partie de l'infrastructure est en cours d'arrêt pour des raisons énergétiques. Par conséquent, il devient nécessaire non seulement d'établir une synergie entre les couches du nuage, mais aussi de rendre ces couches suffisamment souples et sensibles pour être en mesure de réagir aux changements d'exécution et ainsi profiter pleinement de cette synergie. Cette thèse propose une approche d'auto-adaptation qui prend en considération les composants applicatifs (élasticité architecturale) ainsi que d'infrastructure (élasticité des ressources) pour réduire l'empreinte énergétique. Chaque application et l'infrastructure sont équipées d'une boucle de contrôle autonome qui leur permet d'optimiser indépendamment leur fonctionnement. Afin de créer une synergie entre boucles de contrôle autour d'un objectif commun, nous proposons un modèle pour la coordination et la synchronisation de plusieurs boucles de contrôle. L'approche est validée expérimentalement à la fois qualitativement (amélioration de QdS et des gains d'énergie) et quantitativement (passage à l'échelle)

Self-management of applications QoS for energy optimization in datacenters

International audienceAs a direct consequence of the increasing popularity of Cloud Computing solutions, data centers are amazingly growing and hence have to urgently face with the energy consumption issue. Available solutions rely on Cloud Computing models and virtualization techniques to scale up/down application based on their performance metrics. Although those proposals can reduce the energy footprint of applications and by transitivity of cloud infrastructures, they do not consider the internal characteristics of applications to finely de fine a trade-off between applications Quality of Service and energy footprint. In this paper, we propose a self-adaptation approach that considers both application internals and system to reduce the energy footprint in cloud infrastructure. Each application and the infrastructure are equipped with their own control loop, which allows them to autonomously optimize their executions. Simulations show that the approach may lead to appreciable energy savings without interfering on application provider revenues

Self-optimisation of the energy footprint in Service-Oriented Architectures

International audienceThe impact of IT on the global energy consumption has frighteningly increased over the last years. One of the reasons for this is the demand for infrastructure to support the increasing number of online (24x7) services and data, followed by the popularisation of practices like Cloud Computing. From the infrastructure point of view, hardware throttling and server consolidation are techniques used to deal with energy efficiency. However, details about the application behavior are not visible from the infrastructure layer, which prevents a more complete energy-efficient treatment. This paper presents an approach for self-optimisation of the energy consumption at the application layer. We rely on Service-Oriented Architectures, since they allow rapid and seamless service composition and eases the application adaptation. The energy efficiency properties of services are defined by means of Quality of Service criteria and a set of event-condition-actions is defined to enable the application to react to environmental changes and optimise its energy consumption. As a proof of concept, we present a prototype for energy-aware self-adaptation in SOA-based applications as well as an example scenario that shows the practical usage of our approach

Self-management of cloud applications and infrastructure for energy optimization

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Modèles comportementaux pour le contrôle de composants logiciels autonomes

International audienceLes systèmes logiciels modernes et leur architecture doivent s'adapter dynamiquement de façon réactive aux événements provenant de l'environnement (p. ex. la charge de travail demandée par les utilisateurs, les modifications apportées aux fonctionnalités) et de la plate-forme d'exécution (p. ex. les ressources disponibles). Les architectures à base de composants ont montré leur adéquation pour l'auto-adaptation, non seulement en raison de leurs caractéristiques intrinsèques, comme la réutilisation et la modularité, mais aussi en raison de leurs capacités de reconfiguration dynamique. Cependant, les solutions existantes sont basées souvent sur des langages de bas niveau, impératifs, et sans modèle comportemental. Cet article présente Ctrl-F, un langage dédié pour le support de haut niveau pour la spécification des comportements et des politiques d'adaptation dans les système à base de composants logiciels. Nous nous appuyons sur la programmation réactive pour la vérification et le contrôle des reconfigurations. Nous intégrons Ctrl-F avec FraSCAti, une plate-forme intergicielle pour les architectures réparties orientées services

QoS-based Approach for Dynamic Web Service Composition

Web Services have become a standard for integration of systems in distributed environments. By using a set of open interoperability standards, they allow computer-computer interaction, regardless the programming languages and operating systems used. The Semantic Web Services, by its turn, make use of ontologies to describe their functionality in a more structural manner, allowing computers to reason about the information required and provided by them. Such a description also allows dynamic composition of several Web Services, when only one is not able to provide the desired functionality. There are scenarios, however, in which only the functional correctness is not enough to fulfill the user requirements, and a minimum level of quality should be guaranteed by their providers. In this context, this work presents an approach for dynamic Web Service composition that takes into account the composition overall quality. The proposed approach relies on a heuristics to efficiently perform the composition. In order to show the feasibility of the proposed approach, a Web Service composition application prototype was developed and experimented with public test sets, along with another approach that does not consider quality in the composition process. The results have shown that the proposed approach in general finds compositions with more quality, within a reasonable processing time