Storage device including nonvolatile memory device

A storage device comprising:

• a random access memory;
• a nonvolatile memory device including memory blocks;
• and
• a controller configured to perform write, read and erase operations with respect to a selected memory block from among the memory blocks,
• wherein the controller is configured to, based on a number of error bits being greater than a critical value in a read operation with respect to the selected memory block, perform a first read reclaim through at least two migration operations each including reading valid data stored in the selected memory block, storing the valid data in the random access memory, and writing the valid data stored in the random access memory in another memory block of the nonvolatile memory device,
• wherein, in response to the valid data being written to the another memory block, the valid data does not exist in the selected memory block, and
• wherein in the first read reclaim, the controller is configured to adjust an amount of data to be migrated from the selected memory block to the another memory block in one migration operation, among the at least two migration operations, based on reliability of the selected memory block, the reliability indicating a number of times of read operations that can be performed in the selected memory block without losing data of the selected memory block.

A storage device comprising:

• a nonvolatile memory device including memory blocks;
• and
• a controller configured to, based on a number of error bits being greater than a critical value in a read operation with respect to a selected memory block from among the memory blocks, perform a first read reclaim of migrating valid data stored in the selected memory block to another memory block through at least two migration operations,
• wherein, in response to the valid data being migrated to the another memory block, the valid data does not exist in the selected memory block, and
• wherein the controller is configured to adjust an amount of data to be migrated in one migration operation, among the at least two migration operations in the first read reclaim, based on reliability of the selected memory block, the reliability indicating a number of times of read operations that can be performed in the selected memory block without losing data of the selected memory block.