公开(公告)号：JP2004326800A

公开(公告)日：2004-11-18

申请号：JP2004129396

申请日：2004-04-26

Applicant: Internatl Business Mach Corp ,  インターナショナル・ビジネス・マシーンズ・コーポレーションInternational Business Maschines Corporation

Inventor： YOUNG JASON C ,  ANANTHANARAYANAN RAJAGOPAL ,  BURNS RANDAL C ,  LONG DARRELL D E ,  REES ROBERT M ,  BECKER-SZENDY RALPH A ,  SEEGER JAMES J ,  WOLFE DAVID M

IPC: G06F12/00 ,  G06F17/30

CPC classification number: G06F17/30067 ,  Y10S707/959 ,  Y10S707/99953 ,  Y10S707/99955

Abstract: PROBLEM TO BE SOLVED: To provide a system and a method for managing logical versions of a file system made through a near-instantaneous copy process. SOLUTION: Each logical version of the file system, including a primary version, is assigned a unique epoch number or other identifying value, and each file system object is assigned two epoch numbers that define a 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 file system 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 file system objects that are reference by that logical version of file system. Accordingly, new logical versions of file systems are maintained and original states of previous states of the logical versions of file systems are preserved. COPYRIGHT: (C)2005,JPO&NCIPI

公开(公告)号：SG143036A1

公开(公告)日：2008-06-27

申请号：SG2004018016

申请日：2004-03-30

Applicant: IBM

Inventor： YOUNG JASON C ,  ANANTHANARAYANAN RAJAGOPAL ,  BURNS RANDAL C ,  LONG DARRELL D E ,  REES ROBERT M ,  BECKER-SZENDY RALPH A ,  SEEGER JAMES J

IPC: G06F17/30 ,  G06F12/00

Abstract: Managing Filesystem Versions A system and method for managing logical versions of a fdesystem 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 (106) 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 (120). Accordingly, filesystem versions are maintained and original states of previous states of the logical filesystem versions are preserved.