A Performance Study of Robust Distributed Load Sharing Strategies

In this paper, we examine a set of load sharing strategies that are robust to the unreliable state information that is often present in a distributed database system. In this environment, sites must solve the problem of how alternative sites should be selected to process incoming transactions, given that the information on which the decision is based exhibits varying degrees of obsolescence. A set of regression-based adaptive strategies is examined in which a feedback mechanism is used to compensate for obsolete information. Transaction response time under the different adaptive strategies is evaluated, and the reasons for these performance differences discussed. The key characteristic of the best regression strategy is that transaction site affinity is taken into consideration when adjusting for the effect of information obsolescence. © 1994 IEEE