Patent ID: 8612392
Filing Date: 2013-12-17
Classification: G06F

Abstract:
1. A computer program product for processing modifications to a data set in storage, the computer program product comprising a non-transitory computer readable storage medium having computer readable program code embodied therein that executes to perform operations, the operations comprising: maintaining information on a data set of variable length chunks, including a digest of each chunk and information to locate the chunk in the data set; receiving modifications to at least one of the chunks in the data set; determining at least one range of least one of the chunks including data affected by the modifications, wherein each range identifies one chunk or sequential chunks having data affected by the modifications; processing the at least one chunk in each range to determine at least one new chunk in each range, and for each determined new chunk, a digest of the new chunk; determining whether at least one chunk outside of the at least one range has changed; for each determined at least one chunk outside of the at least one range that has changed, determining at least one new chunk and a new digest of the at least one new chunk; and adding to the information the new digest information on the at least one new chunk and information to locate the new chunk in the data set.