The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 20, 2007
Filed:
Feb. 21, 2003
Mark C. Holland, Pittsburgh, PA (US);
Mark C. Holland, Pittsburgh, PA (US);
Panasas, Inc, Pittsburgh, PA (US);
Abstract
A methodology wherein two different types of locks are used by a storage manager when multiple clients wish to access a particular redundantly-stored file. Simple byte-range based mutual exclusion (or mutex) locks are granted by the storage manager for data writes/updates to the file when the file is in the fault-free state, and individual readers/writers (R/W) locks are granted by the storage manager when the file is in the degraded state. No read locks are required of clients when the file object is in the fault-free state. During the fault-free state of the file object, when exactly one client is writing to the file object, the storage manger grants that file object a whole-file lock valid over the entire file object. Each client may have a client lock manager that interacts with appropriate storage manager lock manager to request and obtain necessary locks. These various locking mechanisms reduce lock-related network traffic in a data storage system.