Apparatus and method for memory management

PURPOSE: A memory management device and a method thereof are provided to quickly perform read processing by calculating requested data based on a parity bit and other stripe data even though a disk including the requested data is inaccessible. CONSTITUTION: A data input/output control unit(110) applies a stripe method to a memory including disks to read and write data and determines the performance of read processing through an RAID(Redundant Array of Inexpensive Disks) method according to accessibility to a target disk including read-requested data. If access to the target disk cannot be performed, a request data operation processing unit(140) calculates the requested data according to the RAID method using parity data and stripe data obtained from other striped disks and the target disk. A garbage collection processing unit(130) performs garbage collection processing for the disks. [Reference numerals] (110) Data input/output control unit; (120) Memory; (130) Garbage collection processing unit; (140) Request data operation processing unit;