With the rapid development of cloud computing and big data processing, an increasing number of application frameworks are being considered to run in a “cloud way”. This development brings about several challenges to the enterprise private cloud computing platform, e.g., being able to run most existing heterogeneous applications, providing scalability and elasticity support for newly emerged frameworks, and most importantly, sharing cluster resources effectively. In this paper, we propose a new service model, namely, Cluster as a Service (ClaaS), which is suitable for medium and small-sized data centers to solve these problems in a relatively easy and general way. The idea behind this model is virtualizing the cluster environment for distributed application frameworks. Most applications can directly run in the virtual cluster environment without any modification, which is a great advantage. Based on lightweight containers, we implement a real system of ClaaS named Docklet to prove the feasibility of this service model. Meanwhile, we preliminarily design the definition of applications to make them easy to deploy. Finally, we present several examples and evaluate the entire system.
