Patent ID: 6038619
Filing Date: 2000-03-14
Classification: G06F

Abstract:
A method for managing the movement of data responsive to external read or write requests between an interface and a storage device, the device having either a cyclic, concentric, multitracked storage disk medium or a cyclic, spiral-tracked storage disk medium and means for establishing a path to and copying data from at least one logical block address (LBA) on a counterpart track of said disk responsive to each read request, and for establishing a path to and recording data located on at least one LBA on a counterpart track of the disk responsive to each write request, said path including a circular buffer coupling a disk manager means to an interface manager means, comprising the steps of:(a) establishing a data transfer path including the device interface, the circular buffer, and the disk responsive to a random read or write request and effectuating a datastreaming in a direction consonant with the request;(b) ascertaining whether an immediate successor read or write request is of the same type (read or write) and expresses a sequential or near sequential logical address relationship with its immediate predecessor request wherein(i) a sequential address relationship exists where the starting LBA of an immediate successor request is the next consecutive LBA to the last LBA included in the immediate predecessor request; and(ii) a near sequential address relationship exists where the starting LBA of the immediate successor request lies within a range between the next consecutive LBA to the last LBA included in the immediate predecessor request and a predetermined maximum number K consecutive LBAs; and(c) continuing said datastreaming unabated in a path through and including the circular buffer between the disk and the device interface if the requests match as to type and sequential address relationship, otherwise disabling the path and repeating step (a).