I am trying to use WP Super Cache on a blog I help run. First of all, just wanted to say what a great plugin it is - wouldn't be able to cope without it.
I just had a few questions regarding some problems I've been having lately, and would appreciate anyones help. I'm using the latest release of WP Supercache
As far as I can tell, the cache for the homepage gets invalidated on every post action - even saving drafts, and autosaves? Should this happen?
Also, when publishing a post, the homepage gets the .needs-rebuild extension added, which correctly makes sure the homepage cache gets rebuilt. But from what I can see, the categories that the post is ticked into do not get the .needs-rebuild extension added, so the category index caches dont get rebuild on a post publish. When do the category index caches get updated? For example, should publishing a story into the "uncategorized" category mean the cache for the uncategorized category index gets invalidated?
I also use the enable cache rebuild option - which as I understand it should mean that if I publish a new post, the next person to view the blog will get the old cached version - but WP-SuperCache will create a new cache in the background, while still serving the first person the old cache. Is this a correct understanding? So the first person to visit after a update will get the old cache, but everyone after will get the new cache? Because this doesn't seem to work for me. Even on a test install, publishing a post instantly adds the .cache-rebuild extension to the old cache, then the next person to visit gets the latest version and the cache gets updated with the latest version - the old version never gets served while the new one is created. Is something going wrong?
Finally, I have a question to do with scheduling posts. I schedule posts a lot and have been looking into how it works. When the time for a scheduled post passes, wordpress seems to do nothing until something is viewed - which seems correct. However, as soon as someone visits the homepage after a scheduled post date has passed, WP Super Cache marks the homepage index cache as ".needs-rebuild" - I was just wondering how WP super cache even knows to do this? I should be seeing a cached version of the homepage as directed by the .htaccess file, so the wordpress engine should never even get booted up?
All the above were using a google chrome incognito tab to make sure I didn't have any cookies or other sessions going on.
I'd really appreciate it if someone could try and explain the observations? WP Supercache is critical to me, and I want to try and understand it - as I dont think its a good idea to rely on something so much without knowing how it works, and wanted to look into the few problems I'm having with it.