219 research outputs found
Energy-saving policies in grid computing and smart environments
Texto completo descargado desde TeseoThis work studies the problem of energy consumption growth in two spheres: Grid-Computing and Smart Environments. These problems are tackled through the establishment of energy-saving policies developed for each environment in order to save the maximum energy as possible. In the Grid-Computing environment, seven energypolicies were designed in an attempt to minimize energy consumption through shutting resources down and booting them. It is proved that approximately 40% of energy can be saved. Efficiency of various grid locations was compared using Data Envelopment Analysis methodology. In Smart Environments where sensors perceive lighting conditions, the energy-saving policy adjusts lighting in order to satisfy user preferences and prevents energy from being wasted. A set of wireless sensors were deployed on two offices at the department of Computer Languages and Systems. The dataset created over several months was employed to extract information about user lighting preferences, from the application of which it is proven that around 70% of energy can be saved in lighting appliances.Premio Extraordinario de Doctorado U
Limiting Global Warming by Improving Data-Centre Software
Carbon emissions, greenhouse gases and pollution in general are usually related to traditional factories, so the most modern computing factories have gone unnoticed for the general-public opinion. We empirically show through extensive and realistic simulation that: 1) energy consumption, and consequently CO2 emissions, could be reduced from ~15% to ~60% if the correct energy-efficiency policies are applied; and 2) such energy-consumption reduction can be achieved without negatively impacting the correct operation of these infrastructures. To this end, this work is focused on the proposal and analysis of a set of energy-efficiency policies which are applied to traditional and hyper-scale data centres, as well as numerous operation environments, including: 1) the top resource managers used in industry; 2) eight energy-efficiency policies, including aggressive, fine-tuned and adaptive models; and 3) three types of workload-arrival patterns. Finally, we present a realistic analysis of the environmental impact of the application of such energy-efficiency policies on USA data centres. The presented results estimate that 11.5 million of tons of CO2 could be saved, which is equivalent to the removal of 4.79 million of combustion cars, that is, the total car fleet of countries such as Portugal, Austria and Sweden.Ministerio de Ciencia e Innovación RTI2018-098062-A-I0
Productive Efficiency of Energy-Aware Data Centers
Information technologies must be made aware of the sustainability of cost reduction. Data centers may reach energy consumption levels comparable to many industrial facilities and small-sized towns. Therefore, innovative and transparent energy policies should be applied to improve energy consumption and deliver the best performance. This paper compares, analyzes
and evaluates various energy efficiency policies, which shut down underutilized machines, on an extensive set of data-center environments. Data envelopment analysis (DEA) is then conducted for the detection of the best energy efficiency policy and data-center characterization for each case.
This analysis evaluates energy consumption and performance indicators for natural DEA and constant returns to scale (CRS). We identify the best energy policies and scheduling strategies for high and low data-center demands and for medium-sized and large data-centers; moreover, this work enables
data-center managers to detect inefficiencies and to implement further corrective actions.Universidad de Sevilla 2018/0000052
Quality of cloud services determined by the dynamic management of scheduling models for complex heterogeneous workloads
The quality of services in Cloud Computing (CC)
depends on the scheduling strategies selected for processing of
the complex workloads in the physical cloud clusters. Using
the scheduler of the single type does not guarantee of the
optimal mapping of jobs onto cloud resources, especially in
the case of the processing of the big data workloads. In this
paper, we compare the performances of the cloud schedulers
for various combinations of the cloud workloads with different
characteristics. We define several scenarios where the proper
types of schedulers can be selected from a list of scheduling
models implemented in the system, and used to schedule the
concrete workloads based on the workloads’ parameters and
the feedback on the efficiency of the schedulers. The presented
work is the first step in the development and implementation
of an automatic intelligent scheduler selection system. In our
simple experimental analysis, we confirm the usefulness of such
a system in today’s data-intensive cloud computin
Stackelberg Game-based Models in Energy-aware Cloud Scheduling
Energy-awareness remians the important problem in
today’s cloud computing (CC). Optimization of the
energy consumed in cloud data centers and computing servers is usually related to the scheduling prob lems. It is very difficult to define an optimal schedul ing policy without negoative influence into the system
performance and task completion time. In this work,
we define a general cloud scheduling model based on
a Stackelberg game with the workload scheduler and
energy-efficiency agent as the main players. In this
game, the aim of the scheduler is the minimization of
the makespan of the workload, which is achieved by
the employ of a genetic scheduling algorithm that maps
the workload tasks into the computational nodes. The
energy-efficiency agent selects the energy-optimization
techniques based on the idea of switchin-off of the idle
machines, in response to the scheduler decisions. The
efficiency of the proposed model has been tested using
a SCORE cloud simmulator. Obtained results show
that the proposed model performs better than static
energy-optimization strategies, achieving a fair balance
between low energy consumption and short queue times
and makespan
GAME-SCORE: Game-based energy-aware cloud scheduler and simulator for computational clouds
Energy-awareness remains one of the main concerns for today's cloud computing (CC) operators.
The optimisation of energy consumption in both cloud computational clusters and computing
servers is usually related to scheduling problems. The definition of an optimal scheduling policy
which does not negatively impact to system performance and task completion time is still
challenging. In this work, we present a new simulation tool for cloud computing, GAME-SCORE,
which implements a scheduling model based on the Stackelberg game. This game presents two
main players: a) the scheduler and b) the energy-efficiency agent. We used the GAME-SCORE
simulator to analyse the efficiency of the proposed game-based scheduling model. The obtained
results show that the Stackelberg cloud scheduler performs better than static energy-optimisation
strategies and can achieve a fair balance between low energy consumption and short makespan in
a very short tim
Single-Board-Computer Clusters for Cloudlet Computing in Internet of Things
The number of connected sensors and devices is expected to increase to billions in the near
future. However, centralised cloud-computing data centres present various challenges to meet the
requirements inherent to Internet of Things (IoT) workloads, such as low latency, high throughput
and bandwidth constraints. Edge computing is becoming the standard computing paradigm for
latency-sensitive real-time IoT workloads, since it addresses the aforementioned limitations related
to centralised cloud-computing models. Such a paradigm relies on bringing computation close to
the source of data, which presents serious operational challenges for large-scale cloud-computing
providers. In this work, we present an architecture composed of low-cost Single-Board-Computer
clusters near to data sources, and centralised cloud-computing data centres. The proposed
cost-efficient model may be employed as an alternative to fog computing to meet real-time IoT
workload requirements while keeping scalability. We include an extensive empirical analysis to
assess the suitability of single-board-computer clusters as cost-effective edge-computing micro data
centres. Additionally, we compare the proposed architecture with traditional cloudlet and cloud
architectures, and evaluate them through extensive simulation. We finally show that acquisition costs
can be drastically reduced while keeping performance levels in data-intensive IoT use cases.Ministerio de Economía y Competitividad TIN2017-82113-C2-1-RMinisterio de Economía y Competitividad RTI2018-098062-A-I00European Union’s Horizon 2020 No. 754489Science Foundation Ireland grant 13/RC/209
Energy policies for data-center monolithic schedulers
Cloud computing and data centers that support this paradigm are rapidly evolving in order to satisfy
new demands. These ever-growing needs represent an energy-related challenge to achieve sustainability
and cost reduction. In this paper, we define an expert and intelligent system that applies various en ergy policies. These policies are employed to maximize the energy-efficiency of data-center resources by
simulating a realistic environment and heterogeneous workload in a trustworthy tool. An environmental
and economic impact of around 20% of energy consumption can be saved in high-utilization scenarios
without exerting any noticeable impact on data-center performance if an adequate policy is applied
Machine learning regression to boost scheduling performance in hyper-scale cloud-computing data centres
Data centres increase their size and complexity due to the increasing amount of heterogeneous work loads and patterns to be served. Such a mix of various purpose workloads makes the optimisation of
resource management systems according to temporal or application-level patterns difficult. Data centre operators have developed multiple resource-management models to improve scheduling perfor mance in controlled scenarios. However, the constant evolution of the workloads makes the utilisation
of only one resource-management model sub-optimal in some scenarios.
In this work, we propose: (a) a machine learning regression model based on gradient boosting to pre dict the time a resource manager needs to schedule incoming jobs for a given period; and (b) a resource
management model, Boost, that takes advantage of this regression model to predict the scheduling time
of a catalogue of resource managers so that the most performant can be used for a time span.
The benefits of the proposed resource-management model are analysed by comparing its scheduling
performance KPIs to those provided by the two most popular resource-management models: two level, used by Apache Mesos, and shared-state, employed by Google Borg. Such gains are empirically eval uated by simulating a hyper-scale data centre that executes a realistic synthetically generated workload
that follows real-world trace patternsMinisterio de Ciencia e Innovación RTI2018-098062-A-I0
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