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:
Oct. 28, 2014
Filed:
Jun. 22, 2012
Junping Zhao, Beijing, CN;
Ivan Bassov, Brookline, MA (US);
Kevin Xu, Warren, NJ (US);
Gang Xie, Beijing, CN;
Jialin Yang, Beijing, CN;
Wei Qi, Beijing, CN;
Junping Zhao, Beijing, CN;
Ivan Bassov, Brookline, MA (US);
Kevin Xu, Warren, NJ (US);
Gang Xie, Beijing, CN;
Jialin Yang, Beijing, CN;
Wei Qi, Beijing, CN;
EMC Corporation, Hopkinton, MA (US);
Abstract
A technique performs a write operation. The technique involves receiving, after a snapshot of a file system is taken, a write instruction to write new data to a particular portion of the file system. The technique further involves includes reading, in response to the write instruction, metadata to determine whether the new data is a first update of the particular portion since the snapshot was taken. The metadata identifies portions of the file system which have changed since the snapshot was taken. The technique further involves, when the new data is a first update of the particular portion since the snapshot was taken, copying the original data from cache memory (i.e., from the file system buffer cache) to snapshot storage (i.e., to a dedicated save area) and, after the original data is copied, updating the original data in the cache memory with the new data.