Distributed lock manager for file system objects in a shared file system

摘要

A method and apparatus are provided for mediating access to a shared object in a naive computer system having a shared-nothing operating system layered on a shared file system. At least one primary token is utilized as a tool to mediate ownership of one or more shared objects in the naive system. A secondary token is created and utilized to mediate ownership of one or more shared objects. The secondary token created and utilized in limited circumstances, such as when the owner of the primary token ceases communicating with one or more requesters of the primary token.

主权项

1. A method for managing a shared file system comprising:
establishing a primary token in shared data storage as an element to control access to an object in a shared file system in communication with at least two computer systems in a shared-nothing environment, including a first computer system having a first operating system in communication with a first interface and a second computer system having a second operating system in communication with a second interface, said first operating system different from the second operating system; each of the first and second interfaces coordinating sharing of an object between an associated operating system and the shared file system; the first computer system requesting ownership of said primary token through the first interface, including the first interface searching for the primary token in the shared file system, and identifying a prior owner of said primary token; the first interface receiving a response to said search indicating that said prior owner of said primary token is unavailable; and creating a secondary token in response to receipt of said response, including the first interface taking ownership of said secondary token and transferring the secondary token to the first computer system, wherein the secondary token is created while the primary token is in existence.