Software rejuvenation for resource optimization based on explicit approximate inverse preconditioning

When software applications run continuously, error conditions are accumulated and the result is a degradation of the computer system or even a crash failure. This phenomenon has been reported as software aging. A proactive method in order to counteract this phenomenon is software rejuvenation. In this paper, two software rejuvenation techniques are presented in a computer system in which the amount of free memory is used in order to model the resource degradation of the system. Furthermore, the cost of each technique is determined and the two techniques are compared with respect to the total expected downtime cost of performing rejuvenation and one of them is proposed. In addition, useful results about the rates of performing rejuvenation are derived and finally an optimal rejuvenation policy is proposed for such a computer system.