Information processing apparatus and information processing method

An information processing method performed by a computer including a storage that is configured to store, in a state where a physical storage area in which data requested to be written to a logical storage area is to be stored without duplication is divided into a plurality of partial storage areas, where each of the plurality of partial storage areas includes a plurality of unit storage areas each serving as a data storage unit, and where the plurality of partial storage areas are grouped in a plurality of groups, a management table in which a record associated with each of the unit storage areas is registered, wherein the management table is divided into group regions respectively associated with the plurality of groups, in each of the group regions, the records associated with the unit storage areas included in the partial storage areas belonging to the associated group among the plurality of groups are registered, each of the records contains a first hash value based on data stored in the associated unit storage area and location information of the associated unit storage area,

• the information processing method comprising:
• selecting a first partial storage area as a processing target from among the plurality of partial storage areas;
• identifying a first group to which the first partial storage area belongs among the plurality of groups;
• searching the records included in a first group region associated with the first group among the group regions included in the management table to find a first record associated with each of the unit storage areas included in the first partial storage area, and
• deleting the first hash value included in the first record in a case where the number of references from the logical storage area to data stored in the first partial storage area associated with the searched-out first record is 0.