The Design And Implemention Of Database Subsystem Of The PaaS Cloud Computing System's Simulation Platform

With the development of cloud computing, its scalability, high availability, easy managerial advantages and low costs are widely recognized. PaaS (Platform as a Service) cloud computing system has become an important trend of IT development. However, the direct deployment of applications in real PaaS cloud computing system will bring unnecessary costs. Accordingly, there are requirements to build simulation platform for PaaS cloud computing system. Through the simulation analysis, applications could be deployed in the real PaaS cloud computing system in a right way, avoiding unnecessary waste of resources.In this paper, the characteristics of PaaS cloud computing system are first analyzed and the layered system architecture of PaaS cloud computing system's simulation platform is put forward. The simulation platform is designed of layered and modular structure, constituted of simulation computation subsystem and simulation display subsystem which both have good scalability. The results show that this design has good capability to simulate the real PaaS cloud computing system. And then the simulation platform's database subsystem is described and the design of the database subsystem is proposed, which not only meets simulation platform's existing functions and requirements, but also has good scalability. The database subsystem provides efficient and simple interfaces for simulation computation subsystem and simulation display subsystem. Through the database subsystem, simulation platform could provide the simulation data and statistic analysis, providing references for applications'deployment in the real PaaS cloud computing system.The front-end part of the PaaS cloud computing system's simulation platform is implemented by JavaScript and PHP. The simulation computation subsystem is implemented based on open source software OMNet++. MySQL is adopted as the database. The tests of the simulation platform show that the platform could not only have high performance, but also have good efficiency and stability.The simulation system developed in this project could provide references for applications'deployment in the real PaaS cloud computing system. So the contribution of this project has important practical value for cloud computing's research and development.