Proxy File System (PXFS)

The cluster file system is based on the proxy file system (PXFS), which has the following features:

• PXFS makes file access locations transparent. A process can open a file located anywhere in the system and processes on all nodes can use the same path name to locate a file.

• PXFS uses coherency protocols to preserve the UNIX file access semantics even if the file is accessed concurrently from multiple nodes.

• PXFS provides extensive caching and provides zero-copy bulk I/O movement to move large data objects efficiently.

• PXFS provides continuous access to data, even when failures occur. Applications do not detect failures as long as a path to disks is still operational. This guarantee is maintained for raw disk access and all file system operations.

• PXFS is independent of underlying file system and volume management software. PXFS makes any supported on-disk file system global.

• PXFS is built on top of the existing Solaris file system at the vnode interface. This interface enables PXFS to be implemented without extensive kernel modifications.

PXFS is not a distinct file system type. That is, clients see the underlying file system (for example, UFS).