Load shedding in a data stream management system

摘要

A data stream management system DSMS (110), that receives input data streams (120) from data stream sources and location information associated with the sources and executes a continuous query against data items of the input data streams to generate at least one output data stream (140). The DSMS comprises means (112) to execute a load shedding process when the DSMS is overloaded with data from the input data streams (120) and also includes a learning module (113) that determines , when the DSMS is not overloaded and for the location information associated with the data stream sources , a respective utility value indicating a utility to the DSMS client of data from the data stream sources. The load shedding module (112) identify one or more input data streams whose data items are to be discarded by using location information , together with the location information and data utility values.