How can I do a file cache check on my computer?

Question

How can I do a file cache check on my computer?

Answer 1

The modification time of the cached file is compared with the page_touched field for the given entry in the page table as well as a global $wgCacheEpoch timestamp set in LocalSettings.

If the file is at least as new as both of these, it is considered valid and is sent directly to the client. If it is older or does not exist, parsing and rendering continues and the results are saved for future use.