NOVA: A Log-structured File System for Hybrid Volatile/Non-volatile Main Memories

Fast non-volatile memories (NVMs) will soon appear on the processor memory bus alongside DRAM. The resulting hybrid memory systems will provide software with submicrosecond, high-bandwidth access to persistent data, but managing, accessing, and maintaining consistency for data stored in NVM raises a host of challenges. Existing file systems built for spinning or solid-state disks introduce software overheads that would obscure the performance that NVMs should provide, but proposed file systems for NVMs either incur similar overheads or fail to provide the strong consistency guarantees that applications require. We present NOVA, a file system designed to maximize performance on hybrid memory systems while providing strong consistency guarantees. NOVA adapts conventional log-structured file system techniques to exploit the fast random access that NVMs provide. In particular, it maintains separate logs for each inode to improve concurrency, and stores file data outside the log to mi...

• Type: Journal
• Year: 2016
• Where: FAST
• Authors: Jian Xu, Steven Swanson
• Keywords: FAST 2016, Operating System