System performance

These are global default variables. To edit variables for a specific realm go to Variable Realms

Options related with cache, file compression and bandwidth optimization.

Block caching is inactive if you have enabled modules defining content access restrictions.
Cached pages will not be re-created until at least this much time has elapsed.
The maximum time an external cache can use an old version of a page.
External resources can be optimized automatically, which can reduce both the size and number of requests made to your website.
External resources can be optimized automatically, which can reduce both the size and number of requests made to your website.
External resources can be optimized automatically, which can reduce both the size and number of requests made to your website.