Patent ID: 9477405
Filing Date: 2016-10-25
CPC Classification: G06F,G11C,Y02D

Claim Text:
1. A system comprising: a plurality of storage devices, each of the plurality of storage devices includes a device controller and a plurality of non-volatile semiconductor memory chips, each of the plurality of non-volatile semiconductor memory chips includes a plurality of memory cells, each of the plurality of memory cells store N bits of data, wherein N is a natural number and a value of N is a variable based on a cell mode, wherein a capacity of the storage device is changed based on the cell mode; and a controller configured to: manage a plurality of storage segments which are enabled to store data in a pool provided by the plurality of storage devices, provide a virtual logical unit and allocate a storage segment from the pool to the virtual logical unit in response to receiving a write command to the virtual logical unit, and wherein when the cell mode of at least one of the plurality of storage devices is changed, wherein the controller changes the number of the plurality of storage segments in the pool based on the capacity of the storage device which is changed based on the cell mode of at least one of the plurality of storage devices, and the device controller of one of the plurality of storage devices stores N bits of data into one of the plurality of cells based on the cell mode.