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. 18, 2016
Filed:
Apr. 11, 2013
International Business Machines Corporation, Armonk, NY (US);
Matt R. Hogstrom, Cary, NC (US);
Tiia Salo, Cary, NC (US);
Nikola Vouk, Cary, NC (US);
Meeta Yadav, Cary, NC (US);
INTERNATIONAL BUSINESS MACHINES CORPORATION, Armonk, NY (US);
Abstract
When a virtual machine writes to a page that is being shared across VMs, a share value is calculated to determine how different the page would be if the write command were implemented. If the share value is below a predefined threshold (meaning that the page would not be 'too different'), then the page is not copied (as it would be in a standard copy-on-write operation). Instead, the difference between the contents of the pages is stored as a self-contained delta. The physical to machine memory map is updated to point to the delta, and the delta contains a pointer to the original page. When the VM needs to access the page that was stored as a delta, the delta and the page are then fetched from memory and the page is reconstructed.