ES2: A cloud data storage system for supporting both OLTP and OLAP

Cloud computing represents a paradigm shift driven by the increasing demand of Web based applications for elastic, scalable and efficient system architectures that can efficiently support their ever-growing data volume and large-scale data analysis. A typical data management system has to deal with real-time updates by individual users, and as well as periodical large scale analytical processing, indexing, and data extraction. While such operations may take place in the same domain, the design and development of the systems have somehow evolved independently for transactional and periodical analytical processing. Such a system-level separation has resulted in problems such as data freshness as well as serious data storage redundancy. Ideally, it would be more efficient to apply ad-hoc analytical processing on the same data directly. However, to the best of our knowledge, such an approach has not been adopted in real implementation. Intrigued by such an observation, we have designed and implemented epiC, an elastic power-aware data-itensive Cloud platform for supporting both data intensive analytical operations (ref. as OLAP) and online transactions (ref. as OLTP). In this paper, we present ES² - the elastic data storage system of epiC, which is designed to support both functionalities within the same storage. We present the system architecture and the functions of each system component, and experimental results which demonstrate the efficiency of the system.

I. Introduction

With the increasing popularity of Web 2.0 applications, massive amounts of different types of data are being generated at an unprecedented scale. Given this rate of continuous growth, coupled with advancement in broadband connectivity, virtualization, and other technologies, the cloud computing model, with its capability to dynamically provide for computation and storage, has emerged as an ideal choice for data-intensive and database-as-a-service computing infrastructures. The need to provide for capacity both in terms of storage and computation, and to support online transactional processing and online analytical processing in the cloud, has given rise to major challenges in architecting elastic and efficient data servers.