In this paper we consider the future grid systems built in a large scale open lightpath optical network environment. According to userspsila needs on high performance distributed computation, a group of dedicated lightpaths among the distributed computer resources forming the userspsila on-demand optical grid networks are established dynamically and efficiently providing the high-quality communication capability for users. In such a large scale dynamic and concurrent open network environment, in order to create the best network environment for userspsila applications, we propose an incremental improvement approach to the joint optimization problem of process/processor mapping and logical topology design. Through evaluations, it is shown that this approach is effective and flexible to find the alternative solutions when lightpath provisioning blocking occurs during the userspsila lightpath network construction. In addition, we present two signaling system designs for automatic construction of the users-oriented on-demand optical grid network.