Identifying modified chunks in a data set for storage

• Main Authors: YAKUSHEV MARK L, SMITH MARK A
• Format: Patent
• Language: English
• Published: 17.12.2013
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; PHYSICS

Provided are a computer program product, system, and method for identifying modified chunks in a data set for storage. Information is maintained on a data set of variable length chunks, including a digest of each chunk and information to locate the chunk in the data set. Modifications are received to at least one of the chunks in the data set. A determination is made of 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. The at least one chunk in each range is processed to determine at least one new chunk in each range, and for each determined new chunk, a digest of the new chunk. A determination is made as to 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, a determination is made of at least one new chunk and a new digest of the at least one new chunk. Adding to the set information the new digest information on the at least one new chunk and information to locate the new chunk in the data set.