Abstract: A memory storage device includes a non-volatile memory including a plurality of memory blocks and a memory controller configured to control the non-volatile memory, wherein the memory controller is configured to provide host data including write data to the non-volatile memory, wherein the memory controller is configured to perform a garbage collection operation on the memory blocks to provide garbage collection data to the non-volatile memory when a free block count of the memory blocks is smaller than a first threshold value, and wherein the memory controller is configured to increase a capacity for providing the host data when the free block count of the memory blocks is greater than a second threshold value less than the first threshold value and a valid page count of the first memory block among the memory blocks is less than a third threshold value.