silverstripe-framework/docs/en/topics/caching.md

Caching

Built-In Caches

The framework uses caches to store infrequently changing values. By default, the storage mechanism is simply the filesystem, although other cache backends can be configured. All caches use the [api:SS_Cache] API.

The most common caches are manifests of various resources:

• PHP class locations ([api:SS_ClassManifest])
• Template file locations and compiled templates ([api:SS_TemplateManifest])
• Configuration settings from YAML files ([api:SS_ConfigManifest])
• Language files ([api:i18n])

Flushing the various manifests is performed through a GET parameter (flush=1). Since this action requires more server resources than normal requests, executing the action is limited to the following cases when performed via a web request:

• The environment is in "dev mode"
• A user is logged in with ADMIN permissions
• An error occurs during startup

Custom Caches

See [api:SS_Cache].