Patent ID: 9594525
Date: 2017-03-14
CPC Classifications: G06F

Claim:
1. A data storage device comprising: a data storage unit including a plurality of channels each having a plurality of nonvolatile memory devices; a control unit configured to control a garbage collection operation of selecting a first block included in a first channel as a victim block and copying a valid page included in the first block into a second block included in a second channel that is selected; and a second register configured to store information of one or more channels each having been selected as the second channel, wherein: when there exists one or more channels each having an access count equal to or less than a threshold value, the control unit selects a channel having an access count equal to or less than the threshold value, among the plurality of channels, as the second channel; when there is no channel with an access count equal to or less than the threshold value among the plurality of channels, the control unit selects the second channel among channels whose information is stored in the second register; and wherein: when the second register does not contain information on the second channel, the control unit stores information of the second channel in the second register; when the second register contains information on the second channel, the control unit updates information of the second channel in the second register.