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. 30, 2016
Filed:
Jun. 28, 2013
Emc Corporation, Hopkinton, MA (US);
Jean-Pierre Bono, Westborough, MA (US);
Morgan Clark, South Orange, NJ (US);
Michael Scheer, Summit, NJ (US);
William C. Davenport, Burlington, MA (US);
EMC Corporation, Hopkinton, MA (US);
Abstract
An improved technique involves identifying the location of backed free blocks, i.e., blocks within an upper deck file system that have been provisioned from storage devices of a data storage system to a lower deck file system, allocated from the lower deck file system to the upper deck file system, and later freed from the upper deck file system. A storage processor accesses a set of data structures that identifies backed free blocks as opposed to free blocks that have not been written into and thus do not correspond to any allocated blocks in storage. Once the storage processor identifies the backed free blocks, the storage processor frees each block in the lower deck file system from which the respective backed free block was allocated. The storage processor then updates the set of data structures to indicate that the respective backed free block is now simply a free block.