摘要:
For scalable data deduplication working with small data chunks in a computing environment, for each of the small data chunks, a signature is generated based on a combination of a representation of characters that appear in the small data chunks with a representation of frequencies of the small data chunks. The signature is used to help in selecting the data to be deduplicated.
摘要:
For scalable data deduplication working with small data chunks in a computing environment, for each of the small data chunks, a signature is generated based on a combination of a representation of characters that appear in the small data chunks with a representation of frequencies of the small data chunks. The signature is used to help in selecting the data to be deduplicated.
摘要:
A deduplication storage system enables new input data to be deduplicated with data of synthetic backups already constructed, and for this purpose efficiently calculates deduplication digests for synthetic backups being constructed, based on already existing digests of data referenced by the synthetic backups. For each input data segment of the plurality of input data segments of a synthetic backup being constructed, a plurality of deduplication digests of stored data segments, referenced by the input data segment, is retrieved from an index. Each input data segment is partitioned into each of a plurality of fixed-sized data sub-segments. A calculation is performed producing a deduplication digest for a data sub-segment, where the calculation is based on the retrieved deduplication digests of the plurality of stored data sub-segments referenced by the input data sub-segment.
摘要:
Exemplary method, system, and computer program product embodiments for an incremental modification of an error detection code operation are provided. In one embodiment, by way of example only, for a data block requiring a first error detection code (EDC) value to be calculated and verified and is undergoing modification for at least one randomly positioned sub-blocks that becomes available and modified in independent time intervals, a second EDC value is calculated for each of the randomly positioned sub-blocks. An incremental effect of the second EDC value is applied for calculating the first EDC value and for recalculating the first EDC value upon replacing at least one of the randomly positioned sub-blocks. The resource consumption is proportional to the size of at least one of the randomly positioned sub-blocks that are added and modified. Additional system and computer program product embodiments are disclosed and provide related advantages.
摘要:
A deduplication storage system enables new input data to be deduplicated with data of synthetic backups already constructed, and for this purpose efficiently calculates deduplication digests for synthetic backups being constructed, based on already existing digests of data referenced by the synthetic backups. For each input data segment of the plurality of input data segments of a synthetic backup being constructed, a plurality of deduplication digests of stored data segments, referenced by the input data segment, is retrieved from an index. Each input data segment is partitioned into each of a plurality of fixed-sized data sub-segments. A calculation is performed producing a deduplication digest for a data sub-segment, where the calculation is based on the retrieved deduplication digests of the plurality of stored data sub-segments referenced by the input data sub-segment.
摘要:
A remainder by division of a sequence of bytes interpreted as a first number by a second number is calculated. A first remainder by division associated with a first subset of the sequence of bytes is calculated with a first processor. A second remainder by division associated with a second subset of the sequence of bytes is calculated with a second processor. The calculating of the second remainder by division may occur at least partially during the calculating of the first remainder by division. A third remainder by division is calculated based on the calculating of the first remainder by division and the calculating of the second remainder by division.
摘要:
Exemplary method, system, and computer program product embodiments for full exploitation of parallel processors for data processing are provided. In one embodiment, by way of example only, a set of parallel processors is partitioned into disjoint subsets according to indices of the set of the parallel processors. The size of each of the disjoint subsets corresponds to a number of processors assigned to the processing of the data chunks at one of the layers. Each of the processors are assigned to different layers in different data chunks such that each of processors are busy and the data chunks are fully processed within a number of the time steps equal to the number of the layers. A transition function is devised from the indices of the set of the parallel processors at one time steps to the indices of the set of the parallel processors at a following time step.
摘要:
Methods, computer systems, and computer program products for calculating a remainder by division of a sequence of bytes interpreted as a first number by a second number is provided. A pseudo-remainder by division associated with a first subsequence of the sequence of bytes is calculated. A property of this pseudo-remainder is that the first subsequence of the sequence of bytes, interpreted as a third number, and the pseudo-remainder by division have the same remainder by division when divided by the second number. A second subsequence of the sequence of bytes interpreted as the first number is appended to the pseudo-remainder, interpreted as a sequence of bytes, so as to create a sequence of bytes interpreted as a fourth number. The first number and the fourth number have the same remainder by division when divided by the second number.
摘要:
For full exploitation of parallel processors for data processing, a set of parallel processors is partitioned into disjoint subsets according to indices of the set of the parallel processors. The size of each of the disjoint subsets corresponds to a number of processors assigned to the processing of the data chunks at one of the layers. Each of the processors are assigned to different layers in different data chunks such that each of processors are busy and the data chunks are fully processed within a number of the time steps equal to the number of the layers. A transition function is devised from the indices of the set of the parallel processors at one time steps to the indices of the set of the parallel processors at a following time step.
摘要:
A remainder by division of a sequence of bytes interpreted as a first number by a second number is calculated. A first remainder by division associated with a first subset of the sequence of bytes is calculated with a first processor. A second remainder by division associated with a second subset of the sequence of bytes is calculated with a second processor. The calculating of the second remainder by division may occur at least partially during the calculating of the first remainder by division. A third remainder by division is calculated based on the calculating of the first remainder by division and the calculating of the second remainder by division.