USING REFLECTION FOR INCORPORATING FAULT-TOLERANCE TECHNIQUES INTO DISTRIBUTED APPLICATIONS

Abstract

As part of the Legion metacomputing project, we have developed a reflective model, the Reflective Graph & Event (RGE) model, for incorporating functionality into applications. In this paper we apply the RGE model to the problem of making applications more robust to failures. RGE encourages system developers to express fault-tolerance algorithms in terms of transformations on the data structures that represent computations — messages and methods — hence enabling the construction of generic and reusable fault-tolerance components. We illustrate the expressive power of RGE by encapsulating the following fault-tolerance techniques into RGE components: two-phase commit distributed checkpointing, passive replication, pessimistic method logging, and forward recovery.