Hybrid Storage Systems: A Survey of Architectures and Algorithms

Data center storage architectures face rapidly increasing demands for data volume and quality of service requirements today. Hybrid storage systems have turned out to be the one of the most popular choices in fulfilling these demands. A mixture of various types of storage devices and structures enables architects to address performance and capacity concerns of users within one storage infrastructure. In this paper, we present an extensive literature review on the state-of-the-art research for hybrid storage systems. First, different types of hybrid storage architectures are explored and categorized thoroughly. Second, the corresponding algorithms and policies, such as caching, scheduling, resource allocation and so on, are discussed profoundly. Finally, the advantages and disadvantages of these hybrid storage architectures are compared and analyzed intensively, in terms of system performance, solid state drive lifespan, energy consumption, and so on, in order to motivate some future research directions.