Patent ID: 11941247
Assignee: KIOXIA CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 9:
10. A method, comprising:
managing a plurality of management areas obtained by logically partitioning storage area of a non-volatile memory including a plurality of blocks, each of the blocks being a unit of data erasing, each of the plurality of management areas corresponding to at least one or more blocks of the plurality of blocks;
managing a reference time of a storage device;
when a write request is received that includes data for which a valid term has been set, determining, based on the valid term and the reference time, a first management area from among the plurality of management areas, the valid term being a term during which the data is to be stored in the storage device;
writing the data included in the write request to the determined first management area;
when the data written to the determined first management area is erased, erasing all data written in the first management area which includes the data;
respectively assigning non-overlapping valid terms to the plurality of management areas, the plurality of management areas including the first management area to which a first valid term is assigned and a second management area to which a second valid term longer than the first valid term is assigned;
determining the first management area which has been assigned the valid term that includes an end time of the valid term set for the data included in the write request;
when the first valid term assigned to the first management area has elapsed, shortening the second valid term assigned to the second management area based on the first valid term; and
when the valid term assigned to the first management area to which the data is written has elapsed, collectively erasing all data written to the first management area.