Contract-Based Load Management in Federated Distributed Systems

This paper focuses on load management in looselycoupled federated distributed systems. We present a distributed mechanism for moving load between autonomous participants using bilateral contracts that are negotiated offline and that set bounded prices for moving load. We show that our mechanism has good incentive properties, efficiently redistributes excess load, and has a low overhead in practice. Our load management mechanism is especially wellsuited for distributed stream-processing applications, an emerging class of data-intensive applications that employ a “continuous query processing” model. In this model, streams of data are processed and composed continuously as they arrive rather than after they are indexed and stored. We have implemented the mechanism in the Medusa distributed stream processing system, and we demonstrate its properties using simulations and experiments.