How to scale transactional storage systems

Applications of the future will need to support large numbers of clients and will require scalable storage systems that allow state to be shared reliably. Recent research in distributed file systems provides technology that increases the scalability of storage systems. But file systems only support sharing with weak consistency guarantees and can not support applications that require transactional consistency. The challenge is how to provide scalable storage systems that support transactional applications.We are developing technology for scalable transactional storage systems. Our approach combines scalable caching and coherence techniques developed in serverless file systems and DSM systems, with recovery techniques developed in traditional databases. This position paper describes the design rationale for split caching, a new scalable memory management technique for network-based transactional object storage systems, and fragment reconstruction, a new coherence protocol that supports fine-grained sharing.