Tuple Routing Strategies for Distributed Eddies
نویسندگان
چکیده
Many applications that consist of streams of data are inherently distributed. Since input stream rates and other system parameters such as the amount of available computing resources can fluctuate significantly, a stream query plan must be able to adapt to these changes. Routing tuples between operators of a distributed stream query plan is used in several data stream management systems as an adaptive query optimization technique. The routing policy used can have a significant impact on system performance. In this paper, we use a queuing network to model a distributed stream query plan and define performance metrics for response time and system throughput. We also propose and evaluate several practical routing policies for a distributed stream management system. The performance results of these policies are compared using a discrete event simulator. Finally, we study the impact of the routing policy on system throughput and resource allocation when computing resources can be shared between operators.
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