An Efficient Real-time Concurrency Control Protocol for Guaranteeing Temporal Consistency
نویسندگان
چکیده
A real-time system usually requires maintaining a large amount of temporal data objects. These temporal data objects are accessed by application activities (transactions) to generate the ultimate control actions. In many practical applications, realtime systems require not only ensuring transactions finished in the specified time limits (deadlines), but also guaranteeing temporal consistency of data. In this paper, we first present the formal definitions of temporal consistency for data and transaction. Then, we propose a novel real-time concurrency control protocol (TCHP-2PL), which can guarantee temporal consistency. Further, in order to obtain better real-time performance, the STCHP-2PL, an enhanced version of TCHP-2PL, is proposed by introducing the concept of similarity. Performance test shows that the STCHP-2PL can ensure excellent realtime performance while guaranteeing temporal consistency.
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