Patent ID: 8327097
Filing Date: 2012-12-04
Classification: G06F

Abstract:
1. A method of controlling a plurality of storage-control communication devices for data backup, which are associated with a plurality of storage devices, control the plurality of storage devices, and each of which is communicable with another storage-control communication device via a network, the method comprising: a first step of controlling the plurality of storage-control communication devices for data backup using a de-duplication technique, the first step including: a sub-step of dividing a new file that is to be stored in a first storage device associated with a first storage-control communication device, into a plurality of new data blocks; and a sub-step of storing the new data blocks in the first storage device, such that, when each of at least one of the new data blocks is duplicate to a separate data block, one of the each new data block and the separate data block is selected as a first data block and the other is selected as a second data block, such that the first data block is stored in the first storage device in the form of a real data block, and such that the second data block is stored in the first storage device in the form of a pointer pointing to the real data block stored in the first storage device, not in the form of a real data block, wherein the separate data block is located in a file already stored in the first storage device or another storage device associated with the first storage-control communication device or the new file in the first storage device; a second step of controlling the plurality of storage-control communication devices to define and update a statistical value representative of a history of reference to each data block within previous files loaded into the first storage-control communication device, and to transmit the statistical value to a second storage-control communication device; a third step of controlling the plurality of storage-control communication devices, upon reception of the statistical value from the first storage-control communication device, to select a preloaded data block, based on the received statistical value, and to transmit from the second storage-control communication device to the first storage-control communication device a copying request for making a copy of a real data block stored in the first storage device associated with first storage-control communication device, wherein the real data block to be copied is identical to the preloaded data block; a fourth step of controlling the plurality of storage-control communication devices, upon reception of the copying request from the second storage-control communication device, to make the copy and to transmit the copy to the second storage-control communication device; and a fifth step of controlling the plurality of storage-control communication devices, upon reception of the copy from the first storage-control communication device, to store the copy as the preloaded data block in a second storage device associated with the second storage-control communication device, wherein the first step further includes a sub-step of controlling the plurality of storage-control the communication devices, when a new data block to be newly stored in the associated one of the plurality of storage devices is identical to the preloaded data block already stored in one of the plurality of storage devices, to convert the preloaded data block into a real data block, and to store the new data block in one of the plurality of storage devices in the form of a pointer pointing to the real block data stored in one of the plurality of storage devices, not in the form of a real data block, and wherein the first and second storage-control communication devices are interchangeable and the first and second storage devices are interchangeable.