ArcGIS client APIs allow apps to download map tiles from a server for offline use. Enabling your clients to export cache tiles allows the REST API to perform a series of operations that authorize these downloads. See Export Tiles for more information.
Performing large downloads can negatively impact your server performance and overwhelm the storage of client devices. You can use the Limit export cache setting in ArcGIS Pro to define a maximum number of tiles that a client can request at once and prevent these performance and storage issues. This limit can also be configured using ArcGIS Server Manager.
Tip:
To determine the maximum number of tiles you allow to be downloaded, determining the average area your clients are likely to download and review the total number of tiles in that area.
Exported tiles are placed in the server output directory. When you have enabled clients to export tiles, you may want to increase the maximum allowed age for files in the server output directory, as the default of 10 minutes may not be long enough for the client to retrieve the tiles before they are cleaned. See Edit a server directory in ArcGIS Server Manager for more information. .
Export performance
The REST API uses the caching controller service to export tiles. The number of instances allocated to CachingTools, map, or image services does not affect performance. To increase the number of parallel exportTiles operations supported at any given time, increase the number of instances of the caching controller service. Use the formula 3*N, where N is the number of cores on a single ArcGIS Server machine in the site.