State Street Corporation
Supporting timely data services using fresh data in data-intensive real-time applications, such as e-commerce and transportation management, is desirable but challenging, since the workload may vary dynamically. To control the data service delay to be below the specified threshold, the authors develop a predictive as well as reactive method for database admission control. The predictive method derives the workload bound for admission control in a predictive manner, making no statistical or queuing-theoretic assumptions about workloads. Also, their reactive scheme based on formal feedback control theory continuously adjusts the database load bound to support the delay threshold. By adapting the load bound in a proactive fashion, they attempt to avoid severe overload conditions and excessive delays before they occur.