Modeling Data Center Building Blocks for Energy-efficiency and Thermal Simulations

International audienceIn this paper we present a concept and specification of Data Center Efficiency Building Blocks (DEBBs), which represent hardware components of a data center complemented by descriptions of their energy efficiency. Proposed building blocks contain hardware and thermodynamic models that can be applied to simulate a data center and to evaluate its energy efficiency. DEBBs are available in an open repository being built by the CoolEmAll project. In the paper we illustrate the concept by an example of DEBB defined for the RECS multi-server system including models of its power usage and thermodynamic properties. We also show how these models are affected by specific architecture of modeled hardware and differences between various classes of applications. Proposed models are verified by a comparison to measurements on a real infrastructure. Finally, we demonstrate how DEBBs are used in data center simulations

Computing server power modeling in a data center: survey,taxonomy and performance evaluation

Data centers are large scale, energy-hungry infrastructure serving the increasing computational demands as the world is becoming more connected in smart cities. The emergence of advanced technologies such as cloud-based services, internet of things (IoT) and big data analytics has augmented the growth of global data centers, leading to high energy consumption. This upsurge in energy consumption of the data centers not only incurs the issue of surging high cost (operational and maintenance) but also has an adverse effect on the environment. Dynamic power management in a data center environment requires the cognizance of the correlation between the system and hardware level performance counters and the power consumption. Power consumption modeling exhibits this correlation and is crucial in designing energy-efficient optimization strategies based on resource utilization. Several works in power modeling are proposed and used in the literature. However, these power models have been evaluated using different benchmarking applications, power measurement techniques and error calculation formula on different machines. In this work, we present a taxonomy and evaluation of 24 software-based power models using a unified environment, benchmarking applications, power measurement technique and error formula, with the aim of achieving an objective comparison. We use different servers architectures to assess the impact of heterogeneity on the models' comparison. The performance analysis of these models is elaborated in the paper

Évaluation et optimisation de performance énergétique des centres de calcul

Cette habilitation vise à répondre à la question "Comment gérerefficacement un centre de calcul" en fournissant les outils théoriquesmais aussi pratiques nécessaires. Les centres de calculs sont au coeurde la vie d'une partie croissante de la population sans pour autant êtrevisibles, de par** la prédominance des services en ligne. Leurconsommation électrique est donc un enjeu d'actualité primordial, et lesera encore plus dans le futur prévisible. Gérer efficacement permetdonc d'optimiser la qualité de service tout en réduisant leurconsommation électrique. Ces travaux montrent les différents outilsnécessaires : Ceux liés à la mesure, autant techniquement que de par**la définition des métriques. Ensuite sont explorées les méthodes demodélisation de tels problèmes, ainsi que les techniques de résolutiondirectes ou approchées. L'étape suivante consiste à étudier différentesheuristiques permettant une résolution approchée mais rapide du problèmede la gestion d'un centre de calcul. Diverses validations, autantexpérimentales que basées sur des simulateurs améliorés serviront desupport à ces démonstrations. Une ouverture vers le futur, grâce aux"datacenter in a box" distribués, hétérogènes, coopératifs etmulti-échelles (spatiales et temporelles) conclue ces travaux