Providing Real-Time Response, State Recency and Temporal Consistency in Databases for Rapidly Changing Environments

Abstract Databases have been proposed as the chosen platform to develop automated control systems for environments where the state of the system changes rapidly, and actions need to be taken with timing constraints, such as stock trading, air traffic control, network management and process control. The workload in such systems consists primarily of two types: (a) updates , which report the state of the environment to the database and arrive very frequently, and (b) transactions which arrive with deadlines. In this paper we develop algorithms to install these updates rapidly enough to ensure “state recency” while allocating sufficient resources to transactions to minimize tardiness. We also require that these transactions read temporally consistent data. In summary, this paper contributes in the following three interrelated issues: 1. 1. First and foremost, we look at some interesting problems regarding amalgamating temporal and real-time databases. 2. 2. We look at simultaneous satisfaction of state recency and temporal consistency which are central issues in the class of systems considered in this paper, i.e., rapidly changing systems. 3. 3. We design algorithms that attempt to achieve equilibrium with regard to the conjoint processing of frequently arriving state updates and time constrained transactions. © 1997 Published by Elsevier Science Ltd