Abstract: According to one embodiment, a memory system includes a non-volatile memory, a volatile memory, a controller, and a compression/decompression processor. When data transmission is performed through the volatile memory between a host apparatus and the non-volatile memory, the controller updates management information stored in the volatile memory. In addition, the compression/decompression processor compresses the management information in the case where a first condition is satisfied, and decompresses the compressed management information in the case where a second condition is satisfied. The controller stores the compressed management information in the non-volatile memory.

Abstract: According to one embodiment, a memory system includes nonvolatile memory and storage unit storing a translation table indicating, by a predetermined management unit, relationships between logical addresses specified by a host and physical addresses in the nonvolatile memory. A memory system of the embodiment includes a controller that when receiving from the host a delete notification indicating a delete area smaller than the management unit specified by a logical address, write a specified data pattern to an area of the nonvolatile memory having a physical address corresponding to the delete area.