主权项 |
1. A memory system, comprising:
non-volatile memory that includes a plurality of blocks as a unit of data erase, each one of the plurality of blocks including a plurality of pages as a unit of data write and read; a block management table that stores whether data in the non-volatile memory is valid or invalid in a unit of cluster, the cluster being natural number times as large as a unit of sector, the natural number being equal to or more than two, the unit of sector being a minimum access unit from a host, a size of the cluster being smaller than a size of the block; and a controller configured to:
manage data stored in the non-volatile memory based on the block management table; andexecute compaction based on the block management table, the compaction being a process that reads out a valid cluster from the block and rewrites the valid cluster to an erased block, wherein in the block management table, for each of the blocks, first information related to the likelihood that valid data within the block is invalidated is registered, and the controller is configured to select a block to be a target of the compaction based on the first information and use the selected block to execute the compaction. |