Virtualizing the x86-based data center creates a dynamic environment for server application deployment and resource sharing. Resource management in this environment is challenging as applications are under fluctuating workloads causing diverse resource demands across their tiers. Resource allocation adaptation is essential for high performance machine utilization. This paper presents feedback controllers that dynamically adjust the CPU allocations of multi-tier applications in order to adapt to workload changes by considering the resource coupling between utilizations of application components. Our experimental evaluation on a virtualized 3-tier Rubis server application shows that our techniques work effectively
