Accession Number : ADA292175

Title :   Experimental Evaluation of Dynamic Data Allocation Strategies in a Distributed Database With Changing Workloads.

Descriptive Note : Contractor rept.,

Corporate Author : INSTITUTE FOR COMPUTER APPLICATIONS IN SCIENCE AND ENGINEERING HAMPTON VA

Personal Author(s) : Brunstrom, Anna ; Leutenegger, Scott T. ; Simha, Rahul

PDF Url : ADA292175

Report Date : JAN 1995

Pagination or Media Count : 18

Abstract : Traditionally, allocation of data in distributed database management systems has been determined by off-line analysis and optimization. This technique works well for static database access patterns, but is often inadequate for frequently changing workloads. In this paper we address how to dynamically reallocate data for partionable distributed databases with changing access patterns. Rather than complicated and expensive optimization algorithms, a simple heuristic is presented and shown, via an implementation study, to improve system throughput by 30% in a local area network based system. Based on artificial wide area network delays, we show that dynamic reallocation can improve system throughput by a factor of two and a half for wide area networks. We also show that individual site load must be taken into consideration when reallocating data, and provide a simple policy that incorporates load in the reallocation decision.

Descriptors :   *DATA BASES, *DISTRIBUTED DATA PROCESSING, *WORKLOAD, TEST AND EVALUATION, ALGORITHMS, OPTIMIZATION, POLICIES, DECISION MAKING, STRATEGY, DATA MANAGEMENT, DYNAMICS, SITES, WIDE AREA NETWORKS, PATTERNS, THROUGHPUT, ALLOCATIONS, HEURISTIC METHODS, ACCESS, COMPUTER FILES, STATICS, OFFLINE SYSTEMS.

Subject Categories : Computer Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE