Cache: $wgCacheEpoch
Set this to current time to invalidate all prior cached pages.
Introduced in version:pre 1.1.0
Removed in version:still in use
Allowed values:Date/Time string
Default value:'20030516000000'

Details edit

Set this to a timestamp to invalidate all pages cached prior to that (e.g. to the current time to invalidate all currently cached pages). Affects both client- and server-side caching, including assets controlled by the ResourceLoader .

For a quick copy-paste you can use the following line, whose timestamp is generated via {{CURRENTTIMESTAMP}}:

$wgCacheEpoch = 20231208103545;

If you are using a Unix-like system you can get the current date by entering the following on the command-line:

date +%Y%m%d%H%M%S

To force a file, such as "LocalSettings.php" to be re-read when touched, you can use the following code (MW < 1.17):

# When you make changes to this configuration file, 
# this will make sure that cached pages are cleared.
$wgCacheEpoch = max( $wgCacheEpoch, gmdate( 'YmdHis', @filemtime( __FILE__ ) ) );
Since version 1.17 of MediaWiki, you should use $wgInvalidateCacheOnLocalSettingsChange to automatically invalidate cache whenever "LocalSettings.php" is modified.

See also edit