A storage device includes a host interface, a buffer memory, a storage medium, and a controller. The host interface is configured to receive storage data and an invalidation command, where the invalidation command is indicative of invalid data among the storage data received by the host interface. The buffer memory is configured to temporarily store the storage data received by the host interface. The controller is configured to execute a transcribe operation in which the storage data temporarily stored in the buffer memory is selectively stored in the storage medium. Further, the controller is responsive to receipt of the invalidation command to execute a logging process when a memory capacity of the invalid data indicated by the invalidation command is equal to or greater than a reference capacity, and to execute an invalidation process when the memory capacity of the invalid data is less than the reference capacity. The logging process includes logging a location of the invalid data, and the invalidation process includes invalidating the invalid data.