A non-volatile memory controller, system and method capable of processing a next request as an interrupt before completing a current operation are disclosed. The non-volatile memory system includes a first memory storing meta data loaded from a flash memory; a second memory storing the meta data copied from the first memory; and a flash memory controller copying the meta data from the first memory to the second memory, changing the meta data in the second memory, and then re-copying the changed meta data from the second memory to the first memory during a first-type operation that requires changes in the meta data.