Patent ID: 7627619

Claim:
In a data storage system that stores both database records and ancillary data, a method for processing a request from a host to write a database record to a target location on a logical device associated with a data-storage system in data communication with the host, the logical device having a first set of extents designated for storage of database records and a second set of extents designated for storage of ancillary data, the method comprising: maintaining, at the data storage system, an extent-table having information for distinguishing between the first set of extents and the second set of extents, each of the extents being associated with a corresponding set of processing instructions; based on the information, determining that the target location is on an extent that is designated for storage of a database record, and that the target location is not on an extent that is designated for storage of ancillary data, the ancillary data being different from the database record and not subject to data verification, whereby the database record is not written to an extent that is designated for storage of ancillary data; and writing the database record only to an extent that is designated for storage of a database record.