Storage device including regions of different densities and operation method thereof

A storage device comprising:

• a memory device including a first memory region having a lowest bit density, a second memory region having a medium bit density, and a third memory region having a highest bit density;
• and
• a controller configured to control the memory device,
• wherein the controller is configured to divide and store data, from a host, in the first to third memory regions according to a hotness of the data, is configured to determine candidate blocks among first memory blocks included in the first memory region based on valid page counts (VPCs) or programmed times of the first memory blocks, is configured to select a source block based on hotnesses of plural pieces of unit data stored in the candidate blocks, is configured to select destination blocks in the second and third memory regions, is configured to migrate each piece of unit data stored in the source block to the destination blocks of the second or third memory regions according to a degree of hotness of each piece of the unit data, and is configured to determine the degree of hotness of each piece of the unit data based on reception frequencies of logical addresses corresponding to each piece of the unit data, from the host, and recency of the logical addresses.

An operating method of a storage device including a first memory region having a lowest bit density, a second memory region having a medium bit density, and a third memory region having a highest bit density, comprising:

• determining candidate blocks among first memory blocks included in the first memory region based on valid page counts (VPCs) or programmed times of the first memory blocks, the determining including determining a hotness of each piece of unit data based on reception frequencies of logical addresses corresponding to each piece of the unit data, from a host, and recency of the logical addresses;
• selecting a source block based on hotnesses of plural pieces of unit data stored in the candidate blocks;
• selecting destination blocks in the second and third memory regions;
• and
• migrating each piece of the unit data stored in the source block to the destination blocks of the second or third memory regions according to a degree of hotness of each piece of the unit data.