Cache folder is getting too big

If your cache folder is becoming too large and taking up too much disk space, the first step is to identify which specific folder is getting too big:

wp-content/cache/min

This indicates an issue with the minify/combine of either CSS or JS. By looking at the specific files within the min folder, and whether there are more JS or CSS files, that will reveal which specific option is the issue.

A common issue is with the Combine JS option. We optimize inline JavaScript by default and if your site contains dynamic JS, that is code which varies slightly from page to page, this will trigger a lot of files to be created. 

The solution is either to  exclude the problematic, dynamic Inline JS, or turn off the Combine JS option. 

If your site uses  HTTP/2 combining files is not necessarily recommended.

Note that if the folder already has an excessive number of files in it, you may have to manually remove them via FTP. After doing that and disabling Combine JS, the problem should resolve. 

wp-content/cache/busting

This indicates an issue with the  Remove Query Strings option. 

If you use the Avada theme, disabling their dynamic CSS/JS options can resolve this issue (note, if you're on a multilingual site, you have to disable it for every language). 

Other themes may have similar features where filenames are generated with dynamic names, that is filenames that are unique per page. Disabling that feature of the theme, or the Remove Query Strings option in WP Rocket should resolve it.