HyDrive: Enhancing performance and reliability of storage systems

Most of the data in the world till today has been stored on hard disk drives (HDDs). Though evolution has taken place in HDDs from first IBM’s invention to HDDs till date, in terms of cost, storage size and portability, nothing much development has been seen in its basic internal structure. HDDs still have mechanical components and hence they are power hungry, unreliable, less portable and slower in terms of random performance. Many researchers have started seeing NAND-flash memory as a promising storage media that could revolutionize data storage systems. Replacing HDDs with NAND-flash-based solid state drives (SDDs) is a recently emerging trend for many high-end computing applications. However, due to its high price, low capacity and inability to over-write, a complete replacement of HDDs with SSDs seems to be unreasonable for high-end computing. As new technologies are born, older technologies might take a new role in the process of system evolution. The best results can be achieved in storage systems if both the storage media complement each other in working. We propose a hybrid storage architecture, namely HyDrive, in this research. The HyDrive identifies hot data (data accessed regularly and frequently), and then stores that data on the SSD for faster access. Cold data (less frequently accessed data) will be stored on HDDs, so that the number of write operations issued to SSDs will be controlled and will help to extend SSDs life time. An evaluation of the HyDrive confirms that the HyDrive has a potential to improve present storage architecture. It has potential to improve SSD lifetimes significantly without much affecting the performance. It provides a balance between performance and cost for high-end computing storage systems.