I find changes I make to my site within the panel are immediately live. If I modify one of the php files and ftp to the web host, they take hours top become live. Is there a need to stop and restart php on the host side for updates like this?
If there is a cache directory with files, caching must be enabled.
Thing is, if you update a page via the panel or create a new page etc., the cache is automatically flushed.
If you make any changes to templates, your stylesheets or whatever, you need to empty the cache manually, i.e. remove all files from the cache folder.
Edit: I wonder why there is a cache directory with files in it if cache is not enabled in the config file. Do you happen to use any plugins that cache your pages?