Patent ID: 8996799
Filing Date: 2015-03-31
Classification: G06F

Abstract:
1. A storage system comprising a first storage device and a second storage device configured to retrieve stored data at a higher speed than the first storage device, the storage system also comprising: a feature calculation unit configured to calculate feature data based on a data content of storage target data; a data management unit configured to store the storage target data into the first storage device or the second storage device, and manage a storing position of the storage target data based on the feature data calculated from the storage target data; and a duplication determination unit configured to determine whether or not the same storage target data as the storage target data to be newly stored is already stored in the first storage device based on the feature data calculated from the storage target data, wherein the data management unit is configured to, in a case the duplication determination unit determines that the same storage target data as the storage target data to be newly stored is already stored in the first storage device, not store the storage target data to be newly stored, but refer to the storage target data having already been stored in the first storage device as storage target data to be newly stored, and the storage system further comprising: a duplication number counting unit configured to count a duplication number for each of the storage target data already stored in the first storage device, the duplication number being a number of times of determination by the duplication determination unit that the storage target data is same as the storage target data to be newly stored, wherein: the data management unit is configured to store the storage target data already stored in the first storage device whose duplication number is more than a preset number, into the second storage device.