OCFS2: Native Linux Cluster Filesystem

" summary

OCFS2 is a native Linux cluster filesystem that extends local FS features—POSIX unlink semantics, shared readable mmap, and data consistency—across nodes by layering cluster access. The talk covers the low-level distributed lock manager (DLM), detailed file-system locking (including inode locking and messaging), caching/consistency strategies, per-node JBD metadata journaling and recovery after node failure, and the allocation subsystem: chain allocators for allocation groups, cluster-sized extents for file data, block suballocation for metadata, and dynamically growing block/inode allocators.

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