We study the dynamic power optimization problem in data centers. We formulate and solve the following offline problem: in which slot which server has to be assigned to which job; and in which slot which server has to be switched ON or OFF so that the total power is optimal for some time horizon. We show that the offline problem is a new version of generalized assignment problem including new co...

Datacenters operations are notoriously energy-hungry with the computing and cooling infrastructures drawing comparable amount of power. A direction to improve their efficiency is to jointly control the Information Technology (IT) and Cooling Techniques (CT) components so that less cooling power has to be spent for the same Quality of Service (QoS) level. This work investigates minimum cost cont...

As IT systems are becoming more important everyday, one of the main concerns is that users may face major problems and eventually incur major costs if computing systems do not meet the expected performance requirements: customers expect reliability and performance guarantees, while underperforming systems loose revenues. Even with the adoption of data centers as the hub of IT organizations and ...

In this paper, we develop the optimal minimum-energy scheduler for the dynamic online joint allocation of the task sizes, computing rates, communication rates and communication powers in virtualized Networked Data Centers (NetDCs) that operates under hard per-job delay-constraints. The referred NetDC’s infrastructure is composed by multiple frequency-scalable Virtual Machines (VMs), that are in...

We propose OX, a runtime system that uses application-level availability constraints and application topologies discovered on the fly to enhance resilience to infrastructure anomalies for cloud applications. OX allows application owners to specify groups of highly available virtual machines, following component roles and replication semantics. To discover application topologies, OX monitors net...

Digital Data and Service Centers, such as is envisaged by the ICSU World Data System (WDS), are subject to a wide-ranging collection of requirements and constraints. Many of these requirements are traditionally difficult to assess and to measure objectively and consistently. As a solution to this problem, an approach based on a maturity model is proposed: this adds significant value not only in...

Conventional models for estimating electrical efficiency of data centers are grossly inaccurate for real-world installations. Estimates of electrical losses are typically made by summing the inefficiencies of various electrical devices, such as power and cooling equipment. This paper shows that the values commonly used for estimating equipment inefficiency are quite inaccurate. A simple, more a...

Time and Technology has its significance made us to think and switching from classical to modern era of Information technology. If we look forward to the best of the Industrial world where Technology is the use of Information technology organization especially service based organization, provides a solution telling so and so high approaches. But we know the crackers and hackers may be ethical o...

In the past decade, with the unprecedented growth in tech companies and advances in cloud computing, it has become increasingly common for companies to incorporate virtualization in their data centers to fully utilize their hardware resources. As a result, virtualization and virtualization security have gone through major transforms in the recent years. Virtualization and its unique architectur...

Erasure coding is widely used for massive storage in data centers to achieve high fault tolerance and low storage redundancy. Since the cross-rack communication cost is often high, it is critical to design erasure codes that minimize the cross-rack repair bandwidth during failure repair. In this paper, we analyze the optimal trade-off between storage redundancy and cross-rack repair bandwidth s...