Described is a technique for initialization of a device in a data storage system. A status indicating completion of the initialization is returned after setting initialization indicators associated with tracks of the device. The indicators indicate that the tracks of the device are to be initialized. As subsequent I/O operations for the device are processed, the tracks associated with the subsequent I/O operations are initialized prior to performing the I/O operation if the initialization indicators associated with the tracks are set. A background initialization task scans the initialization indicators and initializes tracks in accordance with the initialization indicators. Once a track has been initialized, its associated initialization indicator is cleared.