초록 ▼

A write interface in a file server provides permission management for concurrent access to data blocks of a file, ensures correct use and update of indirect blocks in a tree of the file, preallocates file blocks when the file is extended, solves access conflicts for concurrent reads and writes to th

A write interface in a file server provides permission management for concurrent access to data blocks of a file, ensures correct use and update of indirect blocks in a tree of the file, preallocates file blocks when the file is extended, solves access conflicts for concurrent reads and writes to the same block, and permits the use of pipelined processors. For example, a write operation includes obtaining a per file allocation mutex (mutually exclusive lock), preallocating a metadata block, releasing the allocation mutex, issuing an asynchronous write request for writing to the file, waiting for the asynchronous write request to complete, obtaining the allocation mutex, committing the preallocated metadata block, and releasing the allocation mutex. Since no locks are held during the writing of data to the on-disk storage and this data write takes the majority of the time, the method enhances concurrency while maintaining data integrity.

대표청구항 ▼

What is claimed is: 1. A method of operating a network file server computer for providing clients with concurrent write access to a file in data storage, the method comprising the network file server computer responding to a concurrent write request from a client by:(a) obtaining a lock for the file

What is claimed is: 1. A method of operating a network file server computer for providing clients with concurrent write access to a file in data storage, the method comprising the network file server computer responding to a concurrent write request from a client by:(a) obtaining a lock for the file; and then(b) preallocating a metadata block for the file; and then(c) releasing the lock for the file; and then(d) asynchronously writing to the file; and then(e) obtaining the lock for the file; and then(f) committing the metadata block to the file in the data storage; and then(g) releasing the lock for the file.