Storage system comprising flash memory modules subject to plural types of wear-leveling processes

A storage system comprising:

• a plurality of flash memory modules, each of the plurality of flash memory modules comprising a memory controller and at least one flash memory chip, the memory controller managing a plurality of blocks provided with the at least one flash memory chip and controlling a first wear-leveling process for leveling erase counts between the plurality of blocks;
• and
• a storage controller coupled to the plurality of flash memory modules, and controlling data sent from a host computer to be sent to a flash memory module of the plurality of flash memory modules,
• the storage controller controlling a second wear-leveling process exchanging data between at least one block of a first flash memory module of the plurality of flash memory modules and at least one block of a second flash memory module of the plurality of flash memory modules.

A storage system comprising:

• a plurality of flash memory modules, each of the plurality of flash memory modules comprising a memory controller and at least one flash memory chip, the memory controller managing a plurality of blocks provided with the at least one flash memory chip and controlling a first wear-leveling process exchanging data between at least two of the plurality of blocks;
• and
• a storage controller coupled to the plurality of flash memory modules, and having a cache memory and controlling data sent from a host computer to be transferred to a flash memory module of the plurality of flash memory modules via the cache memory,
• the storage controller controlling a second wear-leveling process exchanging data between at least one block of a first flash memory module of the plurality of flash memory modules and at least one block of a second flash memory module of the plurality of flash memory modules.