2025/01/09 by Shaobo Li, Li, Shaobo, Yirui Eric Zhou +5 · 1 citation
Computer Science · Decision Sciences · #Advanced Data Storage Technologies #FOS: Computer and information sciences #Operating Systems (cs.OS) #Parallel Computing and Optimization Techniques #Scientific Computing and Data Management
paper · pdf · doi:10.48550/arxiv.2501.04993
openalex publication_date 2025/01/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Unlike non-volatile memory that resides on the processor memory bus, memory-semantic solid-state drives (SSDs) support both byte and block access granularity via PCIe or CXL interconnects. They provide scalable memory capacity using NAND flash at a much lower cost. In addition, they have different performance characteristics for their dual byte/block interface respectively, while offering essential memory semantics for upper-level software. Such a byte-accessible storage device provides new implications on the software system design. In this paper, we develop a new file system, named ByteFS, by rethinking the design primitives of file systems and SSD firmware to exploit the advantages of both byte and block-granular data accesses. ByteFS supports byte-granular data persistence to retain the persistence nature of SSDs. It extends the core data structure of file systems by enabling dual byte/block-granular data accesses. To facilitate the support for byte-granular writes, \pname manages the internal DRAM of SSD firmware in a log-structured manner and enables data coalescing to reduce the unnecessary I/O traffic to flash chips. ByteFS also enables coordinated data caching between the host page cache and SSD cache for best utilizing the precious memory resource. We implement ByteFS on both a real programmable SSD and an emulated memory-semantic SSD for sensitivity study. Compared to state-of-the-art file systems for non-volatile memory and conventional SSDs, ByteFS outperforms them by up to 2.7×, while preserving the essential properties of a file system. ByteFS also reduces the write traffic to SSDs by up to 5.1× by alleviating unnecessary writes caused by both metadata and data updates in file systems.