Providing Safe, User Space Access to Fast, Solid State Disks
Emerging fast, non-volatile memories (e.g., phase change memories, spin-torque MRAMs, and the memristor) reduce storage access latencies by an order of magnitude compared to state-of-the-art flash-based SSDs. This improved performance means that software overheads that had little impact on the performance of flash-based systems can present serious bottlenecks in systems that incorporate these new technologies. The authors describe a novel storage hardware and software architecture that nearly eliminates two sources of this overhead: Entering the kernel and performing file system permission checks. The new architecture provides a private, virtualized interface for each process and moves file system protection checks into hardware.