Problem: Server times out when attempting to access or load a cached map service and tiles in ArcGIS for Server
Attempts to access or load a cached map service and tiles in ArcGIS for Server results in the service experiencing a time-out.
This issue occurs due to incompatible cache formatting in the ArcGIS for Server cache configuration file (conf.xml). The cache is composed of a map service directory that contains a hierarchical collection of tiles (images) and the conf.xml file which stores a description of the cache, known as a tiling scheme.
The StorageFormat parameter located in the conf.xml determines the storage mode of the tiles in the cached map service. This causes the server to experience time-outs when the amount of time it takes to retrieve the cache is lengthy.
Additionally, a cache that is generated for versions prior to the current version of ArcGIS for Server uses a cache format that is incompatible with newer versions. Therefore, there is a mismatch and incompatibility between the cache formats, which leads to the server being unable to load the cached map service.
Solution or Workaround
A workaround for this problem is to rename the StorageFormat parameter in the conf.xml file from esriMapCacheStorageModeCompactV2 to esriMapCacheStorageModeCompact. The conf.xml file can be found at the root folder of the cached map service, for example,
http://serverx.esri.com/arcgiscache/aerial/layers/conf.xmlBy changing the StorageFormat parameter from esriMapCacheStorageModeCompactV2 to esriMapCacheStorageModeCompact, the map service stores caches as tile packets instead of optimized tile bundles. The V2 storage mode stores the cache in tile bundles. Changing the parameter reduces the amount of time required by the system to retrieve the cache, thus reducing the probability of time-outs.
- ArcGIS Help: esriMapCacheStorageFormat Constants
- ArcGIS Help: About ArcGIS caches
- ArcGIS Help: About cached map services