Cache Policy |
With the development of cache technology in SuperMap GIS series products, SuperMap server products also provide multi-faceted support in cache: support HTTP cache, which provides a request cache that covers all service types, and provides three types of tiles for map services: raster, vector, and attribute (obsolete).
Generally speaking, map cache mainly refers to map tiles, but starting from 7C products, the cache of map services includes new vector tiles and attribute tiles (outdated) in addition to the traditional raster tiles.
SuperMap iServer supports enabling Web request cache.
Web request cache is implemented by storing the results of all different requests in memory. You can select whether to enable/disable Web request cache as required. After the Web request cache is enabled, the response result of the request will be automatically cached. When the client sends the same request again, the server will directly return the cached result, thereby improving the service performance.
SuperMap iServer enables Web request cache by default. The cache life cycle is 1 minute. When no same request comes within one minute, the cache will be automatically invalidated. Support Web request cache modules include REST map services and REST 3D service.
Enabling request cache refers to the server-side saving the response results of client requests locally. When the server receives the same request again, it will no longer process it but directly return the response results, which can include map tiles, analysis results, 3D models, etc. Therefore, requesting cache support for full-featured REST services such as maps, data, analytics, and 3D can comprehensively improve server-side response efficiency. The resources that support cache requests for each service are shown in the table below.
Table 1 Services and resources which support Request Cache
| Remote REST service | Resources which support Request Cache | |
| REST map services | entireImage, image, overview, symbol, tileImage | |
| REST data services | features feature statistic Note: Only support the query operations and the getting operation of features. |
|
| REST spatial analyst service | The BufferAnalyst resource | datasetBufferResults, datasetBufferResult, geometryBufferResults, geometryBufferResult |
| The OverlayAnalyst resource | datasetOverlayResults, datasetOverlayResult, geometryOverlayResults, geometryOverlayResult | |
| The resource for extracting isoline | datasetIsolineResults, datasetIsolineResult, geometryIsolineResult, geometryIsoregionResults | |
| The resource for extracting isoregion | datasetIsoregionResults, datasetIsoregionResult, geometryIsoregionResults, geometryIsoregionResult | |
| The interpolation analysis resource | datasetInterpolation、datasetThiessenResults、datasetThiessenResult、interpolationIDW、 interpolationIDWResult、interpolationDensity、interpolationDensityResult、 interpolationRBF、 interpolationRBFResult、interpolationKriging、 interpolationKrigingResult |
|
| The Linear Reference resource | datasetLinearReferencing, generateSpatialData, spatialDataResult | |
| The analysis result set of space relations | datasetGeorelationResults, datasetGeorelationResult | |
| The result set resource of dataset proximity analysis | datasetGeorelationResults, datasetGeorelationResult, geometryThiessennResults, geometryThiessennResult | |
| REST transportation analysis service | TSPPaths, serviceAreas, MTSPPaths, location, closestfacilities, paths | |
| REST traffic transfer service | transferSolutions, transferPath, transferStops, stopListByKeyword | |
| REST 3D service | datas, data, modelIndex, config, dataversion, tiledata | |
The production of map tiles is mainly realized through distributed tiling service , which supports the segmentation of map data into tiles in various formats and stored in various ways, such as raster tiles in MongoDB, SMTiles, UGCV5, etc., vector tiles in SVTiles.
All layers in the map are split and stored as map tiles in raster format, with support forMongoDB distributed storage, SMTiles and MBTiles format, SuperMap UGC format and GeoPackage format.
The SuperMap UGC format is a traditional map tiles format that is common among SuperMap products, and map tiles of the same version can be used universally. The "UGCV5" tile type supported by the distributed tiling service refers to the original cache of version 5.0.
The vector layer in the map is split and stored in the format of vector tiles, which supports the storage in the format of SVTiles.