Here are some features of OCFS2,
- Variable Block and Cluster Sizes – OCFS2 has two main allocation units, blocks and clusters. OCFS2 supports block sizes ranging from 512 bytes to 4 KB and cluster sizes ranging from 4 KB to 1 MB. Cluster size is always greater than or equal to block size.
- Extent-based Allocations – Tracks allocated space in ranges of clusters, making it especially efficient for storing very large files
- Optimized Allocations – Supports sparse files, inline data, unwritten extents, hole punching, REFLINKS, and allocation reservation for higher performance and efficient storage. The REFLINK feature allows you to create multiple writeable snapshots of regular files. It involves an on-disk change. Enable the refcount file system feature to activate.
- Extended Attributes – Supports attaching an unlimited number of name:value pairs to file system objects such as regular files, directories, and symbolic links. Use the setfattr command to attach extended attributes. This feature involves an on-disk change. Enable the xattr file system feature to activate.
- Endian and Architecture Neutral – Supports a cluster of nodes with mixed architectures. The file system allows concurrent mounts on nodes running 32-bit and 64-bit, little-endian (x86, x86_64, ia64) and big-endian (ppc64) architectures.
- Buffered, Direct, Asynchronous, Splice, and Memory Mapped I/Os – Supports all modes of I/Os for maximum flexibility and performance. OCFS2 is fully cache coherent.
- Comprehensive Tools Support – Provides a familiar EXT3-style tool-set that uses similar parameters for ease of use