A server-side tile caching algorithm based on theme temporal and spatial value
LU Ye1,2, ZHANG Wei3, LI Fei3, DU Zhenhong1,2, ZHANG Feng1,2, LIU Renyi1,2
1.Zhejiang Provincial Key Lab of GIS, Zhejiang University, Hangzhou 310028, China 2.Department of Geographic Information Science, Zhejiang University, Hangzhou 310027, China 3.Shandong Provincial Institute of Land Surveying and Mapping, Shandong University, Jinan 250102, China
Abstract：Traditional cache algorithms such as FIFO, LRU, and LFU focus on the access time and frequency of data, while existing tile cache algorithms are mostly applicable to single-type tile data, therefore failing to balance the multi-type and spatial location characteristics of the tile data, and limiting their application on server-side tile caching. By constructing the server-side cache index for multi-type tiles and taking account of the temporal locality, spatial locality and user theme tendency in tile access, a tile data cache replacement algorithm GDTST based on the topic time-space value is proposed. The experimental results show that compared with the traditional server-side cache replacement algorithm, GDTST can improve the cache hit ratio, and has a better latency reduction ratio when the cache capacity is larger, which effectively reduces the load on the tile source server and accelerates the user response speed.
陆晔, 张伟, 李飞, 杜震洪, 张丰, 刘仁义. 一种基于主题时空价值的服务器端瓦片缓存算法[J]. 浙江大学学报（理学版）, 2020, 47(1): 12-19.
LU Ye, ZHANG Wei, LI Fei, DU Zhenhong, ZHANG Feng, LIU Renyi. A server-side tile caching algorithm based on theme temporal and spatial value. Journal of ZheJIang University(Science Edition), 2020, 47(1): 12-19.
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2020, Vol. 47 
