Abstract: A storage device may fetch commands from a plurality of command queues. The storage device may determine a policy for fetching commands from the plurality of command queues as a first policy or a second policy on the basis of the state of a target command queue among the plurality of command queues. The policy may control an order in which commands are fetched from the plurality of command queues.

Abstract: The present technology relates to an electronic device. According to the present technology, a host device may include a garbage collection controller and an idle time processor. The garbage collection controller may provide, to a storage device, a health information request command for requesting health information including a host write amount and a storage device write amount, provide, to the storage device, a first garbage collection control command for requesting garbage collection cost information based on the health information, provide, to the storage device, a second garbage collection control command for instructing to perform garbage collection based on the garbage collection cost information and an idle time of the storage device. The idle time processor may process information on the idle time.

Abstract: The present technology includes a controller controlling an operation of a semiconductor memory device in response to a test request received from an external device. The controller includes a memory test controller and a performance information storage. The memory test controller generates a command corresponding to a test request received from the external device. The performance information storage stores a test operation result of the semiconductor memory device performed in response to the command.