WebGIS中带图业务数据的缓存和预取机制研究

Research on Caching and Prefetching Business Data with Pictures in WebGIS

目前在WebGIS中地图缓存已得到深入的关注和研究.随着WebGIS客户端性能的逐渐增强,如图片音频等越来越丰富的内容也能被展示出来;由于服务端磁盘读取和网络传输两大瓶颈,一定程度上延长了用户访问这些资源的等待时间;以某高速公路管理系统为背景系统,采用了在服务端和客户端各加一组业务数据缓存、客户端启动后预先读取服务端缓存的方式,提高了带图片的业务数据的访问性能;同时根据该WebGIS中业务数据特有的地理位置关系,在分析用户访问轨迹后,客户端预测用户可能访问的下一条数据并预取,进一步提高了缓存性能。

Currently in WebGIS map cache has been deeply concerned and researched.With the increase of WebGIS client performance,WebGIS can show more rich content,such as pictures,audio and other media.The server reading disk and network transmission are two major bottlenecks,have partly extended the delay of user access to these resources.A highway management system for the background of the system.Added sets of business data caching in server and clients,and enable clients prefetch server＇s cache after started up.have improved the performance of access business data with pictures.According the geographical relations of business data in thisWebGIS,after analyzed users＇ accessing tracks,prefetching the next data that users may access improved cache performance further.