Config changes invalidating cache
This value can be changed to tune the size of the cache for your system.Ehcache caches are implemented using a linked-map system, which means that memory is only required for objects that are actually in memory.Some comments may show the approximate amount of Java heap memory required by the cache.Some object references are shared by the caches, so the amount of memory used is not as high as the approximate value may suggest.If you set the affects the permanent memory taken up by the cache.If the caches grow too large, they may crowd out transient session memory and slow down the system. By default, output cache is not invalidated on changing the page permissions. We do not recommend deselecting this option, because any change of permissions will invalidate the output cache of all pages.
IIS also detects changes to the files when you make updates, and IIS flushes the cache as needed.
Important You can invalidate most types of objects that are served by a web distribution, but you cannot invalidate media files in the Microsoft Smooth Streaming format when you have enabled Smooth Streaming for the corresponding cache behavior.
In addition, you cannot invalidate objects that are served by an RTMP distribution.
Sitefinity exposes a class called and, if you wanted to inject dynamic content onto cached pages, you can take advantage of this infrastructure without hindering performance.
You can disable caching page by page and you can also leverage the post-cache substitution mechanism.