Method for initialization of storage systems
A method and apparatus are described for providing initialization in large storage systems as a background function, upon demand, and upon receipt of write requests. The initialization may be carried out under control of the hard disk drive itself, a storage controller, or both systems. The initialization is performed transparently to the host computer making operation of the storage system immediately after it is coupled to the host feasible.
1. A method of preparing storage media in a storage system for data to be written to the storage media, wherein the system is prepared for writing data to the storage media in both of the following two ways:
initialization of portions of the storage media are performed as a background job in which input/output requests and initialization are executed as background jobs; and
otherwise any un-initialized portions of the storage media to which write requests are directed are initialized prior to writing data in response to write requests that are received by the system for writing the data to the storage media portions.
2. A method as in claim 1 wherein the initialization is performed upon receipt of a command from a controller controlling the storage system.
3. A method as in claim 1 , further including:
performing a resume operation for reconstructing data.
4. A method as in claim 1 wherein portions of the storage media are not initialized when the system is first used.
5. A method as in claim 1 wherein the system includes a storage controller and disk drives, and wherein initialization is controlled by at least one of the storage controller and the disk drives.
6. A method as in claim 5 wherein the storage controller maintains control data for controlling the initialization by storing it in a non-volatile memory.
7. A method as in claim 6 wherein the storage controller controls the initialization, and the disk drives initialize themselves upon receiving a command from the storage controller.