Patent ID: 9665293
Date: 2017-05-30
CPC Classifications: G06F

Claim:
1. A method for managing data in a hierarchical storage device which includes primary storage disks and secondary storage disks, wherein the primary storage disks have higher performance than the secondary storage disks, the method performed by the storage device comprising: detecting an access frequency of a data block stored in the secondary storage disks; determining that the access frequency of the data block reaches an access threshold value; moving the data block to the primary storage disks based upon determining that the access frequency of the data block reaches the access threshold value; dividing the data block in the primary storage disks into a plurality of sub-blocks, wherein the sub-blocks are independently accessible, and wherein each of the sub-blocks has a respective access frequency separate from access frequencies of other sub-blocks; detecting the access frequencies of the sub-blocks; and moving a sub-block back to the secondary storage disks when an access frequency of the sub-block is less than the access threshold value.