Guarantee the Quality-of-Service of Control Transactions in Real-Time Database Systems

Abstract

Temporal consistency analysis is an important problem in Real-Time Database Systems (RTDBSs). Most of existing works on hybrid transaction co-scheduling focus on exploring effective deadline and period assignment methods which can guarantee the temporal consistency of data objects and the schedulability of transactions. To the best of our knowledge, all existing researches have not yet invested sufficient efforts on guaranteeing the Quality of Service (QoS) of control transactions and allow control transactions finish their execution after the data obtained by these control transactions expire. In this paper, we define a new problem of how to schedule a hybrid transaction set under the guarantee on QoS of control transactions. Two deadline and period assignment methods for addressing the defined problem are proposed in this work. Both the proposed methods support the Earliest Deadline First (EDF) scheduling. Extensive experiments are conducted to evaluate the performances of the proposed methods in terms of acceptance ratio, processor workload and efficiency. INDEX TERMS Real-time database systems, QoS of control transactions, hybrid transaction set, the EDF scheduling, deadline and period assignment.

Dynamic channel allocation strategy for quality of service enhancement in wireless ad hoc networks

“…The algorithm requires the scheduler to select the task with the earliest deadline and allocate the resources that are needed to perform the task. 20 To the EDF algorithm, we can easily owe the discovery that the queuing delay of interrupted or waiting business is related to its priority and deadline. Hence, the computation method of packet queuing delay with k priority can be defined as…”

“…The earlier the deadline is, the higher its priority is. The algorithm requires the scheduler to select the task with the earliest deadline and allocate the resources that are needed to perform the task 20 . To the EDF algorithm, we can easily owe the discovery that the queuing delay of interrupted or waiting business is related to its priority and deadline.…”

rocorl: Transferable Reinforcement Learning-Based Robust Control for Cyber-Physical Systems With Limited Data Updates

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