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:
Aug. 31, 2010
Filed:
Jul. 31, 2007
Xia Xu, Boise, ID (US);
Aaron Lindemann, Boise, ID (US);
Xia Xu, Boise, ID (US);
Aaron Lindemann, Boise, ID (US);
Hewlett-Packard Development Company, L.P., Houston, TX (US);
Abstract
Various embodiments of the present invention are directed to an instant snapshot-tree-copy operation that, when directed to an existing snapshot tree, generates a data-structure framework for a copy of the existing snapshot tree that can be immediately accessed while a background-copy process copies data from the existing snapshot tree to the copy snapshot tree. The background-copy process copies data from the existing snapshot tree to the copy snapshot tree in top-down fashion, from the source logical device through each of the snapshot logical devices. While copying each logical device, the background-copy process sequentially copies data-storage units from a corresponding logical device of the existing snapshot tree to the copy-snapshot-tree logical device, making sure to adjust chains of dependencies within the copy snapshot tree to reflect modifications to the snapshot copy tree that occur independently from the background-copy process. A host computer may immediately access the copy snapshot tree, both for READ and WRITE access, even before completion of the background-copy process.