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:
Feb. 24, 2009
Filed:
Nov. 13, 2006
David Alan Burton, Vail, AZ (US);
Noel Simen Otterness, Lafayette, CO (US);
David Alan Burton, Vail, AZ (US);
Noel Simen Otterness, Lafayette, CO (US);
Pillar Data Systems, Inc., San Jose, CA (US);
Abstract
The invention relates to methods of snapshot operation for a data storage system with a host communicating with a cache memory, a source Virtual Logical Unit Number (VLUN) and a target VLUN, including generating first metadata (e.g., bitmaps and log files pointers) to locate first snapshot data and to indicate when the first snapshot data is in the target VLUN and generating second metadata to locate second snapshot data and to indicate when the second snapshot data is in the target VLUN, wherein the first and second metadata locate the same data in the target VLUN. The invention relates to systems that implement the methods. It relates to destaging data to maintain data consistency including reading metadata for snapshots, searching the metadata to identify snapshots that require original data to be destaged, destaging the original data to target storage, and updating metadata to locate original data and indicate destage completion.