An effective cache management algorithm of three-dimensional spatial data engine

Traditional substitution algorithms for cache management are more unitary, and basically each algorithm only has correspondingly good effect on certain type of access pattern. Based on analyzing the characteristics of spatial data, a new approach is proposed for cache replacement, considering both frequency and the duration of hit comprehensively. The criterion function of substitution algorithm can be adjusted by statistics of database querying condition combined with the system resource usage, so that the cache would have high performance, and competition for system resources could be reduced. This paper described three sub-algorithms of cache management algorithm, which are substitution algorithm based on hit frequency and duration, cache pool management algorithm and object incidence query algorithm. The cache management algorithm has been implemented on the cache management module of three-dimensional spatial data engine and applied in the three-dimensional data processing of urban planning of Wuhan. It has been proved that the cache management algorithm could be used in multi-level buffering structure and object-oriented spatial database management system to improve the capability of spatial data dispatch.