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:
Nov. 21, 2006
Filed:
Apr. 29, 2003
Jason C. Young, Portland, OR (US);
Rajagopal Ananthanarayanan, Milpitas, CA (US);
Randal C. Burns, Washington, DC (US);
Darrell D. E. Long, Soquel, CA (US);
Robert M. Rees, Los Gatos, CA (US);
Ralph A. Becker-szendy, Los Gatos, CA (US);
James J. Seeger, Portland, OR (US);
David M. Wolfe, Portland, OR (US);
Jason C. Young, Portland, OR (US);
Rajagopal Ananthanarayanan, Milpitas, CA (US);
Randal C. Burns, Washington, DC (US);
Darrell D. E. Long, Soquel, CA (US);
Robert M. Rees, Los Gatos, CA (US);
Ralph A. Becker-Szendy, Los Gatos, CA (US);
James J. Seeger, Portland, OR (US);
David M. Wolfe, Portland, OR (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A system and method for managing logical versions of a filesystem made through a near-instantaneous copy process is provided. Each logical version of the filesystem, including the primary version, is assigned a unique epoch number or other identifying value, and each filesystem object is assigned two epoch numbers that define the space of logical versions for which the object exists. A list of all valid epoch numbers are maintained in a version table. The near-instantaneous creation of a logical version of the filesystem requires inserting a unique epoch number entry in the version table () and the next epoch number to the new logical version. An original state of the system is preserved through the use of a copy-on-write procedure for filesystem objects that are reference by that logical filesystem version (). Accordingly, filesystem versions are maintained and original states of previous states of the logical filesystem versions are preserved.