Control device, control method, and program

A control device comprising:

• a reading and writing control unit configured to control writing and reading of data on and from a non-volatile memory that has a plurality of blocks each set to be a unit for performing erasure of data;
• and
• an allotment unit configured to allot a logical Translation Unit (TU) to a physical TU,
• wherein each of the blocks has a plurality of pages each set to be a unit for performing writing and reading of data,
• wherein, by setting a unit for performing logical-physical conversion in which a logical memory area is converted into a physical memory area to be a TU, the non-volatile memory stores logical TU numbers specifying logical TUs which are logical TUs allotted to physical TUs, in the physical TUs which are physical TUs each of which includes one or more of the pages,
• wherein a predetermined physical TU among the physical TUs included in the block stores all of the logical TU numbers of the logical TUs each allotted to the physical TUs included in the block when the logical TUs are allotted to all of the physical TUs included in the block, and
• wherein, when the number of blocks in which writing of data is completed is not equal to or higher than a threshold value decided in advance, the allotment unit allots the logical TUs to all physical TUs to which the logical TUs are not allotted, among physical TUs included in a block of interest to be noted selected from the blocks that include writing-unperformed physical TUs, and the reading and writing control unit writes all of the logical TU numbers of the logical TUs each allotted to the physical TUs included in the block of interest, in the predetermined physical TU included in the block of interest.