Specification and management of QoS in real-time databases supporting imprecise computations

Amirijoo, Mehdi; Hansson, Jörgen; Son, Sang H.

doi:10.1109/tc.2006.45

Cited by 89 publications

(95 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In [4], a feedback control mechanism was proposed to schedule update transactions together with user transactions from applications to deal with unpredictable workload and transient overloading. It divides the workload into mandatory and optional, and tries to identify which ones should be scheduled using feedback control, based on the pre-defined QoS metrics.…”

Section: Related Workmentioning

confidence: 99%

An effective fixed priority co-scheduling algorithm for periodic update and application transactions

et al. 2012

View full text Add to dashboard Cite

An important function of many Cyber-Physical Systems (CPS) is to provide a close monitoring of the operation environment to be able to adapt to changing situations effectively. One of the commonly applied techniques for that is to invoke time-constrained periodic application transactions to check the status of the operation environment. The status of the environment is represented by the values of the physical entities in the operation environment which are maintained as real-time data objects in a real-time database. Unfortunately, meeting the deadlines of application transactions and maintaining the quality of real-time data objects are conflicting with each other, because they compete for the same computation resources. To address this problem of update and application transactions co-scheduling problem, in this paper, we propose a fixed priority co-scheduling algorithm called Periodic Co-Scheduling ( PCS). PCS uses periodic update transactions to maintain the temporal validity of real-time data objects. It judiciously decides the priority orders among all the update and application transactions so that the constructed schedule can satisfy the deadline constraints of all the application transactions and at the same time maximize the qualities of the real-time data objects to ensure the correct execution of application transactions. The effectiveness of the algorithm is validated through extensive simulation experiments.

show abstract

Section: Related Workmentioning

confidence: 99%

An effective fixed priority co-scheduling algorithm for periodic update and application transactions

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Based on H R , we can observe whether workloads exceed the operating range. Also, we intentionally generate bursty workloads that exceed H R to test the robustness of realtime data services under stress in Section V. Despite the importance, most existing work on feedback control of real-time data service performance, including [4], [3], [5], [6], [7], does not consider the reliability of real-time data services beyond the operating range.…”

Section: Feedback Control Designmentioning

confidence: 99%

“…To enhance the quality of real-time data services even in the presence of dynamic workloads, formal feedback control theory [1], [2] has been applied [3], [4], [5]. In these closed-loop approaches, system dynamics are approximated in a piecewise linear manner over a finite operating range of workloads for system modeling [1].…”

Section: Introductionmentioning

confidence: 99%

“…• As a result, the integrated approach is more adaptive to dynamic workloads compared to feedback-only approaches for real-time data services such as [4], [3], [5], [6], [7]. This is a key feature needed to improve the quality of real-time data services in dynamic environment.…”

Section: Introductionmentioning

confidence: 99%

“…We extend the Berkeley DB [8] (an open source database from Oracle) to support real-time data services via the feed-forward and feedback schemes. The tested workloads are not only within but also beyond the operating range to explore the system behaviors extensively, unlike most existing work on feedback control of real-time data services [4], [3], [5], [6], [7] that only considers workloads within the operating range. The open-loop approach, i.e., the unmodified Berkeley DB, and feed-forward-only approach based on the CLT fail to support the desired data service delay bound even for relatively light workloads.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Integrating Proactive and Reactive Approaches for Robust Real-Time Data Services

Zhou

Kang

2009

2009 30th IEEE Real-Time Systems Symposium

View full text Add to dashboard Cite

Abstract-Real-time data services are needed in data-intensive real-time applications such as e-commerce or traffic control. However, it is challenging to support real-time data services, if workloads dynamically change based on the market or traffic status. To enhance the quality of real-time data services even in the presence of dynamic workloads, feedback control theory has been applied. However, a major drawback of feedback control is that it only reacts to performance errors. To improve the robustness of realtime data services, we develop a statistical feed-forward approach that proactively adapts the incoming load, if necessary, to support the desired real-time data service delay. Further, we integrate it with a feedback controller to compensate potential prediction errors and adjust the system behavior in a reactive manner for timely data services. Performance evaluation results acquired in our real-time data service testbed show that our integrated approach considerably reduces the average delay and transient delay fluctuations, while improving throughput compared to the tested baselines including the feed-forward-only and feedbackonly approaches.

show abstract

Real Time Database Systems

Lindström¹

2008

Wiley Encyclopedia of Computer Science and Engineering

View full text Add to dashboard Cite

A real‐time database system (RTDBS) is a database system designed to handle workloads whose state is constantly changing. This system differs from traditional databases containing persistent data, mostly unaffected by time. A real‐time database is a database in which transactions have deadlines or timing constraints. Real‐time databases are commonly used in real‐time computing applications that require timely access to data. In this article, we will discuss the most important concepts of real‐time database systems.

show abstract

Specification and management of QoS in real-time databases supporting imprecise computations

Cited by 89 publications

References 21 publications

An effective fixed priority co-scheduling algorithm for periodic update and application transactions

An effective fixed priority co-scheduling algorithm for periodic update and application transactions

Integrating Proactive and Reactive Approaches for Robust Real-Time Data Services

Real Time Database Systems

Contact Info

Product

Resources

About