Patent ID: 8489611
Filing Date: 2013-07-16
Classification: G06F,H03M

Abstract:
1. A computer readable medium storing computer executable instructions that when executed by a computer control the computer to perform a method, the method comprising: computing a first hash for a chunk for which a duplicate determination is to be made, where the duplicate chunk determination is a function of the first hash being compared to a stored first hash, the stored first hash being stored in a first index; selectively determining a type of delta hash to compute based on one or more of, chunk entropy, chunk size, chunk type, and a recently determinative delta hash; selectively determining how many delta hashes to compute based on one or more of, chunk entropy, chunk size, and chunk type; computing a delta hash for the chunk, where a delta chunk determination is to be made for the chunk, where the delta chunk determination is a function of the delta hash being compared to a stored delta hash, the stored delta hash being stored in a second, different index; upon determining that the first hash matches a stored first hash, controlling a deduplication logic to process the chunk as a duplicate; and upon determining that the first hash does not match a stored first hash and that the delta hash matches a stored delta hash, controlling the de-duplication logic to process the chunk as a delta chunk, where the first hash and the delta hash are computed in parallel, where determining that the first hash matches a stored first hash and determining that the delta hash matches a stored delta hash proceeds in parallel, where a definitive answer concerning the first hash causes termination of the determination proceeding in parallel concerning the delta hash, and where a definitive answer concerning the delta hash causes termination of the determination proceeding in parallel concerning the first hash.