Coordination issues in multi-agent event data processing

Abstract

We present a multi-agent systems approach to distributed event-data processing as it is pervasive in scientific computing environments. The task investigated is the one of configuration and execution of event-data processing pipelines to be assembled from single computational services (agents) that perform an asynchronous mapping of streams of inputs to streams of outputs, where the specification is given by characterizing the final output of a pipeline. Comprehensive declarative descriptions of the capabilities of single agents in such systems can be shown to be computationally intractable because of the complexity of the mapping between inputs and outputs of individual agents. We therefore investigate the consequences of circumventing this problem by publishing just the output capabilities of agents, performing the transformation of output requirements to input requirements opaquely within individual agents, and utilizing recursive runtime contracting to configure complete data processing pipelines. The information loss entailed by this kind of information propagation opens up the possibility of pipeline misconfigurations that in turn lead to runtime exceptions when constraints between interfaces that were not explicitly enforced by the published capability descriptions are violated. We characterize the ensuing coordination needs and related design requirements for such kinds of multi-agent systems and propose the introduction of social laws as a promising principled solution approach to be further researched. © Springer-Verlag Berlin Heidelberg 2000.