1. A dispersed storage (DS) unit comprises: a processing module; and a plurality of hard drives, wherein the processing module is operable to: maintain states for at least some of the plurality of hard drives; receive a memory access request regarding an encoded data slice; identify a hard drive of the plurality of hard drives based on the memory access request; determine a state of the hard drive; when the hard drive is in a read state and the memory access request is a write request: queue the write request; change from the read state to a write state in accordance with a state transition process; and when in the write state, perform the write request to store the encoded data slice in the hard drive.