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Design, Implementation, and Evaluation of a QoS-Aware Real-Time Embedded Database
January 2012 (vol. 61 no. 1)
pp. 45-59
Woochul Kang, University of Virginia
Sang Hyuk Son, University of Virginia, Charlottesville
John A. Stankovic, University of Virginia University of Virginia University of Virginia, Charlottesville Charlottesville Charlottesville
Quality-aware realtime Embedded DataBase (QeDB) is a database for data-intensive real-time applications running on embedded devices. Currently, databases for embedded systems are best effort, providing no guarantees on their timeliness and data freshness. Existing real-time database (RTDB) technology cannot be applied to these embedded databases since it hypothesizes that the main memory of a system is large enough to hold the entire database. This, however, might not be true in data-intensive real-time applications. QeDB uses a novel feedback control scheme to support QoS in such embedded systems without requiring all data to reside in main memory. In particular, our approach is based on simultaneous control of both I/O and CPU resources to guarantee the desired timeliness. Unlike existing work on feedback control of RTDB performance, we implement and evaluate the proposed scheme on a modern embedded device. The experimental results show that our approach supports the desired timeliness of transactions while still maintaining high data freshness compared to baseline approaches.

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Index Terms:
Real-time database, embedded database, transaction tardiness, sensor data freshness, QoS management, feedback control, Multiple Input/Multiple Output (MIMO) control.
Woochul Kang, Sang Hyuk Son, John A. Stankovic, "Design, Implementation, and Evaluation of a QoS-Aware Real-Time Embedded Database," IEEE Transactions on Computers, vol. 61, no. 1, pp. 45-59, Jan. 2012, doi:10.1109/TC.2010.240
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