Lira: Lightweight, Region-aware Load Shedding in Mobile CQ Systems

Position updates and query re-evaluations are two predominant, costly components of processing location-based, continual queries (CQs) in mobile systems. To obtain high-quality query results, the query processor usually demands receiving frequent position updates from the mobile nodes. However, processing frequent updates oftentimes causes the query processor to become overloaded, under which updates must be dropped randomly, bringing down the quality of query results, negating the benefits of frequent position updates. In this paper, we develop LIRA - a lightweight, region-aware load-shedding technique for preventively reducing the position-update load of a query processor, while maintaining high-quality query results. Instead of having to receive too many updates and then randomly drop some of them, LIRA uses a region-aware partitioning mechanism to identify the most beneficial shedding regions to cut down the position updates sent by the mobile nodes within those regions. Based on ...

• Type: Conference
• Year: 2007
• Where: ICDE
• Authors: Bugra Gedik, Ling Liu, Kun-Lung Wu, Philip S. Yu
• Keywords: Database, Frequent Position Updates, ICDE 2007, Query Processor, Query Re-evaluations