Patent ID: 7971093
Filing Date: 2011-06-28
Classification: G06F

Abstract:
1. A method to evaluate input/output (I/O) performance of a hard disk drive in a mass storage computer system, and to maintain efficiency in executing I/O commands, the hard disk drive having multiple tracks and multiple sectors in each track, the method comprising: addressing I/O commands to the sectors; evaluating execution of the I/O commands to the sectors to obtain performance information for the sectors to which the I/O commands are addressed; associating the performance information with the sectors to which the I/O commands are addressed; comparing the performance information to a predetermined I/O performance criterion; identifying any impaired sectors in which the performance information indicates less performance than the predetermined I/O performance criterion; storing I/O completion times for the impaired sectors in a data table; determining a range of sectors addressed by each I/O command; accessing the data table of stored I/O completion times to obtain the I/O completion times for the range of sectors addressed by the I/O command; predicting a completion time of the I/O command using the I/O completion times obtained from the data table; dispatching the I/O command to the hard disk drive when the predicted completion time is less than a predetermined timeout; and servicing the I/O command by an alternate process when the predicted completion time of the I/O command is not less than the predetermined timeout.