Value-Based Scheduling for Multiprocessor Real-Time Database Systems

摘要

We present a new scheduling policy named Value-based Processor Allocation (VPA-κ) for scheduling value- based transactions in a multiprocessor real-time database system. The value of a transaction represents the profit the transaction contributes to the system if it is completed before its deadline. Using VPA-κ policy, the transactions with higher values are given higher priorities to execute first, while at most κpercentage of the total processors are allocated to the urgent transactions dynami- cally. Through simulation experiments, VPA-κ policy is shown to outperform other scheduling policies substantially in both max- imizing the totally obtained values and minimizing the number of missed transactions.