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:
Sep. 11, 2007
Filed:
Dec. 09, 2004
Saurabh Agarwal, New Delhi, IN;
Rahul Garg, Ghaziabad, IN;
Meeta S Gupta, Champaign, IL (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method, apparatus and computer program product are disclosed for incrementally checkpointing the state of a computer memory in the presence of at least one executing software application at periodic instants. A secure hash function is periodically applied to each partitioned contiguous block of memory to give a periodic block hash value. At each periodic instant, a block hash value for each block is compared with a respective preceding block hash value to determine if said memory block has changed according to whether said block hash values are different. Only changed memory blocks are stored in a checkpoint record. The memory block sizes are adapted at each periodic instant to split changed blocks into at least two parts and to merge only two non-changed contiguous blocks at a time.