CrossFS: Improving Cross-Domain File System Performance with CRDT-Based Metadata Synchronization

Modern data-intensive applications increasingly demand efficient and scalable file systems that can operate across distributed and cross-domain environments. However, existing file systems are inefficient in metadata management, synchronization efficiency, and system scalability under high-concurrency and metadata-intensive workloads in cross-domain environments. To address these challenges, this paper introduces CrossFS (CFS), a cross-domain distributed file system that enhances consistency guarantees and metadata indexing. Specifically, CFS leverages conflict-free replicated data types (CRDTs) to synchronize metadata, achieving strong eventual consistency with minimal synchronization overhead, even across network partitions. Furthermore, CFS employs a Hybrid Tree indexing structure, tailored for distributed environments, which optimizes metadata operations by reducing query latency by up to 33.4% and write amplification by 30.7%. Additionally, CFS achieves adaptive caching strategies and a hybrid synchronization model that effectively balances consistency latency with data availability. Extensive evaluations show that CFS outperforms CephFS and GlusterFS, achieving up to 33.9% higher metadata throughput, 36% lower latency, and 42% better data operation efficiency.