Self-managing SLA compliance in cloud architectures: a market-based approach

Abstract

Service providers often use service level agreements (SLAs) to assure potential users of their services about the QoS to expect when they subscribe. In the cloud computing model, providers are required to continuously meet their SLA claims in the face of unanticipated failure of cloud resources. The dynamics of the cloud environment as attributed to its unpredictable mode of use and elasticity of its resources make human-driven solutions inefficient or sometimes infeasible. On the other hand, self-managed architectures have increasingly matured in their capacity to coordinate environments predominated by uncertainties. Thus making them a right fit for managing cloud-based systems. However, given the massive resource pool of the cloud, state-of-the-art centralised self-managed architectures are not scalable and are inherently brittle. Therefore, we propose a decentralised resource control mechanism which meets the unique robustness, scalability and resilience requirements of the cloud. The design of the mechanism gains inspiration from market control theory and a novel use of reputation metrics. In addition, an innovative self-managed cloud architecture has been designed based on the control mechanism. Early results from simulation studies show that the approach is feasible at reducing the SLA violations incurred by cloud providers.