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:
Apr. 27, 2021
Filed:
Jul. 21, 2017
Emc Ip Holding Company Llc, Hopkinton, MA (US);
Ying Hu, Northborough, MA (US);
Anton Kucherov, Milford, MA (US);
Zvi Schneider, Hod Hasharon, IL;
Vladimir Shveidel, Pardes-Hana, IL;
Xiangping Chen, Sherborn, MA (US);
Felix Shvaiger, Brighton, MA (US);
EMC IP Holding Company LLC, Hopkinton, MA (US);
Abstract
An apparatus comprises a storage system having storage devices and an associated storage controller. In conjunction with initiation of a checkpoint, the storage controller sets a checkpoint started flag for the checkpoint, marks user data pages and metadata pages for write operations already entered in a write journal of the storage system as of the setting of the checkpoint started flag as checkpoint pages, and marks user data pages and metadata pages for new write operations entered in the write journal after the setting of the checkpoint started flag as non-checkpoint pages by altering information used to generate signatures for respective ones of the metadata pages. Metadata pages characterizing the same user data pages subject to write operations at different times thereby have different signatures depending on whether or not the checkpoint started flag was set when its corresponding write operation was entered in the write journal.