ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

MIRROR: a state-conscious concurrency control protocol for replicated real-time databases

Xiong, Ming and Ramamritham, Krithi and Haritsa, Jayant R and Stankovic, John A (2002) MIRROR: a state-conscious concurrency control protocol for replicated real-time databases. In: Information Systems, 27 (4). pp. 277-297.


Download (414kB)


Data replication can help database systems meet the stringent temporal constraints of current real-time applications, especially Web-based directory and electronic commerce services. A prerequisite for realizing the benefits of replication, however, is the development of high-performance concurrency control mechanisms. In this paper, we present managing isolation in replicated real-time object repositories (MIRROR), a concurrency control protocol specifically designed for firm-deadline applications operating on replicated real-time databases. MIRROR augments the classical O2PL concurrency control protocol with a novel state-based real-time conflict resolution mechanism. In this scheme, the choice of conflict resolution method is a dynamic function of the states of the distributed transactions involved in the conflict. A feature of the design is that acquiring the state knowledge does not require inter-site communication or synchronization, nor does it require modifications to the two-phase commit protocol. Using a detailed simulation model, we compare MIRROR's performance against the real-time versions of a representative set of classical replica concurrency control protocols for a range of transaction workloads and system configurations. Our performance studies show that (a) the relative performance characteristics of these protocols in the real-time environment can be significantly different from their performance in a traditional (non- real-time) database system, (b) MIRROR provides the best performance in both fully and partially replicated environments for real-time applications with low to moderate update frequencies, and (c) MIRROR's simple to implement conflict resolution mechanism works almost as well as more sophisticated strategies.

Item Type: Journal Article
Publication: Information Systems
Publisher: Elsevier Science Ltd.
Additional Information: The copyright of this article belongs to Elsevier Science Ltd.
Keywords: concurrency control;data replication;real time transaction processing;two phase commit;two phase locking (2PL);optimistic concurrency control(OCC);optimistic two phase locking(O2PL)
Department/Centre: Division of Interdisciplinary Sciences > Supercomputer Education & Research Centre
Date Deposited: 17 Jul 2004
Last Modified: 19 Sep 2010 04:14
URI: http://eprints.iisc.ac.in/id/eprint/1054

Actions (login required)

View Item View Item