Memory controller for controlling background operation and operation method thereof

An operation method of a memory controller that communicates with a memory device comprising a plurality of blocks, the method comprising:

• triggering a background operation on a first block among the plurality of blocks according to an error detecting result of data read from at least one first page of the first block;
• setting an input/output (IO) ratio between a host IO operation that exchanges data with the memory device in response to a request from a host and an internal IO operation that exchanges data with the memory device in relation to a background operation on the memory device, as a first value according to a health grade of the first block, wherein the health grade of the first block is determined based on block information related to a determination of a degree of degradation of the first block and an error detecting result of data read from at least one second page of the first block, and wherein based on the health grade of the first block being different from a health grade of a second block among the plurality of blocks, the IO ratio of the first block is set differently from an IO ratio of the second block and a frequency of performing the host IO operation for the first block is different from a frequency of performing the host IO operation for the second block;
• and
• performing the host IO operation and the internal IO operation with the memory device according to the IO ratio set as the first value, during a period in which the background operation on the first block is performed.

A storage device comprising:

• a nonvolatile memory device comprising a plurality of blocks;
• and
• a memory controller configured to perform a host input/output (IO) operation that exchanges data with the nonvolatile memory device in response to a request from a host and an internal IO operation that exchanges data with the nonvolatile memory device in relation to a background operation on the nonvolatile memory device,
• wherein the memory controller is further configured to
• set, as a first value, a performing ratio of the internal IO operation to the host IO operation with respect to a first block among the plurality of blocks based on block information related to determination of a degree of degradation of the first block and a first error detecting result, and
• set, as a second value, a performing ratio of the internal IO operation to the host IO operation with respect to a second block among the plurality of blocks based on block information related to determination of a degree of degradation of the second block and a second error detecting result, and
• based on the first value being greater than the second value, a speed of a background operation on the first block is faster than a speed of a background operation on the second block.