Pruning Update Log Files in Intermittently Connected Databases

Liton Chakraborty, Ajit Singh, Kshirasagar Naik

Abstract

Modern databases allow mobile clients that subscribe to replicated data, to process the replica without requiring continuous connectivity, and to receive the updates while connected to the server. In such an environment—usually known as the Intermittently Connected Database (ICDB) system—the server should maintain the updates to the database in the log file(s). These update log files should be pruned to reduce update retrieval time. In this paper we propose two pruning algorithms, based on the periodic connectivity of the clients, that consider two scenarios: uniform client connectivity patterns and widely varying client connectivity patterns. In the former case, the complete pruning algorithm is effective in keeping the log file size within a bound, hence reducing both disk I/O during update propagation, and disk storage space; whereas, in case of the latter, the partial pruning algorithm achieves significant further reduction in disk I/O while retrieving the updates. Any reduction in CPU or I/O time in turn reduces wireless connection time for each client resulting in significant savings in time and costs. Experimental results demonstrate the effectiveness of these algorithms.

References

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Paper Citation


in Harvard Style

Chakraborty L., Singh A. and Naik K. (2004). Pruning Update Log Files in Intermittently Connected Databases . In Proceedings of the 3rd International Workshop on Wireless Information Systems - Volume 1: WIS, (ICEIS 2004) ISBN 972-8865-02-3, pages 63-72. DOI: 10.5220/0002666100630072


in Bibtex Style

@conference{wis04,
author={Liton Chakraborty and Ajit Singh and Kshirasagar Naik},
title={Pruning Update Log Files in Intermittently Connected Databases},
booktitle={Proceedings of the 3rd International Workshop on Wireless Information Systems - Volume 1: WIS, (ICEIS 2004)},
year={2004},
pages={63-72},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0002666100630072},
isbn={972-8865-02-3},
}


in EndNote Style

TY - CONF
JO - Proceedings of the 3rd International Workshop on Wireless Information Systems - Volume 1: WIS, (ICEIS 2004)
TI - Pruning Update Log Files in Intermittently Connected Databases
SN - 972-8865-02-3
AU - Chakraborty L.
AU - Singh A.
AU - Naik K.
PY - 2004
SP - 63
EP - 72
DO - 10.5220/0002666100630072