Computing system and method of operating the same

A method of operating a host device, the method comprising:

• providing, to a storage device, a health information request command for requesting health information including a host write amount and a storage device write amount;
• providing, to the storage device, a first garbage collection control command for requesting garbage collection cost information based on the health information received from the storage device;
• and
• providing, to the storage device, a second garbage collection control command instructing to perform garbage collection based on the garbage collection cost information and an idle time of the storage device.

A storage device comprising:

• a memory device including a plurality of memory blocks;
• and
• a memory controller configured to
• provide, in response to a health information request command from an external device, the external device with health information including an external device write amount and a storage device write amount,
• provide, in response to a first garbage collection control command from the external device, the external device with garbage collection cost information including an expected number of free blocks to be secured by garbage collection, and
• perform the garbage collection on the memory device in response to a second garbage collection control command from the external device.