Optimal refactoring policy for agile information systems maintenance : A control theoretic approach

Many information systems development companies are facing the question on how to apply agile methods in information systems maintenance (ISM). Performing correction of software defects in ISM inevitably degenerates program structure. On the other hand, agile methods provide refactoring to improve program structure without changing its behavior. This paper builds an optimal control model to balance the tradeoff between defect correction and refactoring. We answer three questions. First, is that optimal to perform parallel defect correction and refactoring? Second, how to determine the iteration length for agile ISM if team wants to include refactoring in the iteration? Third, how long the iteration should be if team wants to improve program's structure to a certain level at the end of the iteration? To our knowledge, this paper is the pioneer in understanding agile ISM policy analytically. Managerial implications of the results are also discussed in the paper. © (2011) by the AIS/ICIS Administrative Office All rights reserved.