Resources Allocation in Virtualized Systems Based on Try- Before-Buy Approach

In virtualization environments, resources are shared across multiple virtual machines(VMs), which results in contentions and even conflicting under heavily loaded or consolidated situations. In order to accommodate as many as service instances while still delivering performance guarantees, resource allocation should be optimized in a just adequate manner such that less resources will be utilized for a specific performance requirement. To achieve this goal, in this paper we propose a try-before-buy approach for allocating contending resources. This approach firstly does a try of minor resource allocation to find the performance feedback and search for the optimal amount of resource that should be allocated to the target virtual machine. This approach does not require a highly accurate performance model in a virtualized system where workloads usually change frequently with time in some intervals. Experiments on a Xen based virtualized environment are conducted and evaluated for its effectiveness. The results show that the proposed approach utilizes less CPU and memory resources to achieve the same performance goals compared to default Xen configuration with over-provisioning.