THE OPTIMAL PREVENTIVE MAINTENANCE POLICY FOR A SOFTWARE SYSTEM WITH MULTI SERVER STATION

摘要

The purpose of this article is to consider the optimal preventive maintenance policy for a software system which is operated on a multi server station. Suppose that the performance of the servers degrades gradually and tends to break down as they keep operating successively. This phenomenon can be regarded as the aging in reliability theory. Based on the familiar Markovian analysis, three reliability measures: steady-state availability, probability of loss of transactions and expected response time of a transaction, are formulated. In a numerical example, we calculate the optimal preventive maintenance policy.