Seeding a tile cacheΒΆ
A tile can be generated in two ways:
- By the system administrator, usually in an automatic batch operation
- By the user, who generates individual tiles by requesting ones not already cached
In both cases, the method of generation remains the same on the server side: a request is sent to the source WMS, which is returned and stored in the tile cache.
The first case, generating tiles by the system administrator in a batch operation, is known as “seeding”. This section will discuss considerations involved when seeding a cache in advance, as well as how to execute those requests.
- Seeding considerations
- Determining whether or not to seed
- Determining image format
- Determining coordinate reference system
- Determining tile dimensions
- Determining metatiling
- Determining to what level to seed the full extent
- Determining areas of interest
- Determining to what zoom level to seed each area of interest
- Preparing the seed tasks
- Determining tile expiration and reseeding
- Seeding a tile cache through the web interface