Power-aware server consolidation for federated clouds

Cloud computing has evolved to provide computing resources on-demand through a virtualized infrastructure, letting applications, computing power, data storage, and network resources to be provisioned and managed over private networks or over the Internet. Cloud services normally run on large data centers and demand a huge amount of electricity. Consequently, the electricity cost represents one of the major concerns of data centers, since it is sometimes nonlinear with the capacity of the data centers, and it is also associated with a high amount of carbon emission (CO2). However, energy-saving schemes that result in too much degradation of the system performance or in violations of service-level agreement (SLA) parameters would eventually cause the users to move to another cloud provider. Thus, there is a need to reach a balance between energy savings and the costs incurred by these savings in the execution of the applications. Therefore, in this paper we propose and evaluate a power and SLA-aware application consolidation solution for cloud federations. It comprises a multi-agent system (MAS) for server consolidation, taking into account service-level agreement, power consumption, and carbon footprint. Different for similar solutions available in the literature, in our solution, when a cloud is overloaded its data center needs to negotiate with other data centers before migrating the workload to another cloud. Simulation results show that our approach can reduce up to 46% of the power consumption while trying to meet performance requirements. Furthermore, we show that federated clouds can provide an adequate solution to deal with power consumption in the clouds. Copyright c © 0000 John Wiley & Sons, Ltd.