Query Quality of Service Management Based on Data Relationship over Real-Time Data Stream Systems

Many real-time applications and data services in distributed environments need to operate on continuous unbounded data streams with the development of large wired and wireless sensor network. Conventional one-time queries cannot be suitable to provide continues results as data and update stream into the system, and continuous queries represent a new paradigm for interacting with dynamically changing data. At the same time, many real-time applications have inherent timing constraints in their tasks, so providing data objects deadline guarantees for continuous queries over dynamic data streams is a challenging problem. A novel performance metric and quality of service management scheme continuous queries over dynamic data streams are proposed to guarantee system performance based on relationship of all updated data items. Experimental simulations demonstrate that the presented algorithm can guarantee the performance and decrease miss ratios of queries for dynamic workload fluctuations especially transient overloads.