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:
Jul. 07, 2009
Filed:
Nov. 10, 2007
Fernando Oliveira, Sudbury, MA (US);
Jeffrey A. Schriesheim, Lexington, MA (US);
Fernando Oliveira, Sudbury, MA (US);
Jeffrey A. Schriesheim, Lexington, MA (US);
EMC Corporation, Hopkinton, MA (US);
Abstract
Described are techniques used in connection with providing continuous data backups of primary storage. A first technique uses distributed partial journals and a copy of the primary storage. A distributed partial journal is used for each input port. The partial journals are periodically incorporated into a main journal in accordance with a time stamp for the data modification recorded in each partial journal entry. A second technique, a copy on write, uses the distributed partial journals without requiring a copy of the primary storage. For each write to an address, the current contents of the address is journaled before the address on primary storage is updated.