Patent ID: 8332581

Claim:
A method for managing deleted data volumes in a storage system, each volume including at least one track, each track including a plurality of records including a first record R 0 and at least a second record R 1 , the first record R 0 including a data field being in a state of all zeros when the track is uninitialized and the second record R 1 for storing user data, a volume being in an initialized state and may be reused when a track format description (TFD) in metadata stored in a cache and associated with the tracks on the volume is zeroed leaving prior, stale user data in the storage space of the deleted volume, the method comprising: creating a new volume to reuse the storage space of a deleted volume; upon a determination that the TFD for the deleted volume is invalid: staging a track from the storage space used by the deleted volume into the cache; attempting to read the first record R 0 of the staged track; determining whether the first record R 0 is stale; if the first record R 0 is stale, determining whether the second record R 1 of the staged track is stale; if the second record R 1 is stale: zeroing the first sector of the first record R 0 to uninitialize the first record R 0 ; and modifying the TFD in the cache to indicate that the staged track is uninitialized; and if the second record R 1 is not stale: indicating that the first record R 0 is invalid or corrupted; regenerating the first record R 0 based on its physical location; and modifying the TFD in the cache to indicate that the staged track is initialized.