Abstract: A data storage device includes a cumulative data histogram of lengths of idle times between foreground user service requests. The cumulative data histogram is updated with measured lengths of current idle times between successive user service requests. Background service request are scheduled following a user service request after a time delay that is controlled as a function of the cumulative data histogram and a calculated length of a busy time of the background service request.

Abstract: A data storage device includes a cumulative data histogram of lengths of idle times between foreground user service requests. The cumulative data histogram is updated with measured lengths of current idle times between successive user service requests. Background service request are scheduled following a user service request after a time delay that is controlled as a function of the cumulative data histogram and a calculated length of a busy time of the background service request.

Abstract: A method for processing requests in a data storage system, the method comprising: receiving a plurality of requests, each of the requests including a block address; and determining if successive ones of the requests are sequential stream requests by using arrival times of the successive requests and the block addresses of the successive requests. The method can also determine if disc workload is sequential or random, and requests can be selected to be postponed based on the workload characteristics in the case of overload when admission control is needed to achieve gradual degradation in performance. Apparatus that performs the method is also provided.

Abstract: A method for processing requests for information from a disc drive comprising: (a) receiving a plurality of requests, wherein each of the requests has application level information associated with it; (b) identifying a first group of the requests that fit within a time interval; (c) using a scheduling algorithm with disc information to schedule one of the requests in the first group; (d) adjusting the length of the time interval; (e) identifying another group of the requests that fit within the adjusted time interval; (f) using the scheduling algorithm to schedule one of the requests in the other group; and (g) repeating steps (d), (e) and (f). An apparatus that processes requests for information in accordance with the method is also provided.

Abstract: A method for processing requests for information from a disc drive comprising: (a) receiving a plurality of requests, wherein each of the requests has application level information associated with it; (b) identifying a first group of the requests that fit within a time interval; (c) using a scheduling algorithm with disc information to schedule one of the requests in the first group; (d) adjusting the length of the time interval; (e) identifying another group of the requests that fit within the adjusted time interval; (f) using the scheduling algorithm to schedule one of the requests in the other group; and (g) repeating steps (d), (e) and (f). An apparatus that processes requests for information in accordance with the method is also provided.