Ok, let me explain what's going on in this situation and what are the issues.
1. That's great news! It seems Rocket uses the WordPress core clean_post_cache() function and resets the cache when this function is called, so it understands wpForo calls. In recent versions of wpForo we optimized the cache and it calls clean_post_cache() function when some data is changed and the page cache should be reset to update information on forums and topics. So Rocket starts to understand when reset forum page based on wpForo correct requests to resetting cache. However I'm not sure it's 100% correct yet. Because you've disabled it for logged-in users and we don't know if it displays correct data for guests.
2. Rocket cache loads cached HTML file. In other words, you see a html screenshot of the forum page. And this is only for guests, for speed checkers, for search engine bots... However it does nothing when you're logged-in, because you've disabled it for private logged in user cache. So you don't see any issue when you're loggedin because Rocket is disabled and it does nothing. Here comes wpForo cache, you should enable back wpForo Object, Memory and Member cache, they'll work for logged-in users when the Rocket is disabled, even if it's enabled they should be enabled too, because they don't conflict.
3. Rocket cannot do any smart and intuitive cache for wpForo forum core, because wpForo system is out of standard WP post types. Rocket cache only take a HTML screenshot and loads it when you call the page, so it's fast, but the data of that page may not be dynamic. Make sure you check it as guest. As I said above when you're logged-in Rocket doesn't work.
4. The page loading speed mostly depends on loading media. wpForo with its cache is fast, however on forum page there are many avatars, they come from other plugins or form Gravatar and they affect page speed heavily. So the plugin performance is great and the cache works fine. Also there are many JS libs from external services which makes it slower too. For example reCAPTCHA, Twitter, Facebook, etc...
@robert thanks very much for the detailed explanation. I'm taking your recommendations on board - keeping WP-Rocket and the wpForo caching mechanisms active 😀
@robert your post got me thinking. WP-Super Cache (Automattic) uses for sure clean_post_cache() so i did some tests.
Seems to work and update things. Not 100% sure if it updates everything, i will test more and update here. I have left the wpForo cache enable except the HTML cache.
I may have to tinker with this a bit too. I'm pretty happy with my GTMetrix results, but I'm sure they could be improved. I've spent a lot of time trying to make the site as clean as possible to help with load times, and I've been rewarded greatly for that... I went from 8-second load times to 4.4-second load times and the only caching installed on the site is that included with wpForo. I'm also using CloudFlare with some of the advanced caching and minifying tools activated and the host itself has some sort of caching in place. But if WP Rocket gets me to 3 seconds or less, it's probably worth it. Thanks for the info and discussion!
Just circling back to this with an update for those interested.
I'm now running Cloudflare, WP-Rocket, and wpForo - all of which are working in perfect harmony together. Cloudflare is not caching static content, but does leverage it's CDN to deliver the necessary assets. WP-Rocket is performing caching and minification. I'm also using HTTP/2 SPDY and sockets, meaning that https://inocul8r.net runs like......er, well.... a rocket... 🙂
Just circling back to this with an update for those interested.
I'm now running Cloudflare, WP-Rocket, and wpForo - all of which are working in perfect harmony together. Cloudflare is not caching static content, but does leverage it's CDN to deliver the necessary assets. WP-Rocket is performing caching and minification. I'm also using HTTP/2 SPDY and sockets, meaning that https://inocul8r.net runs like......er, well.... a rocket... 🙂
Nice to know all that. It seems that WPRocket is a good plugin.
I have tried to use also myself the minifying options of LiteSpeed cache and while it works fine, for some reason it makes my site slower. I suspect because i'm on a shared (but premium plan).
@anonymous20 strange you should say that. I tried minifcation etc under LS Cache, and it either didn't make any difference at all, or caused issues. I should point out that I have a paid plan with Cloudflare (GBP 20.00 for the pro plan, GBP 5.00 for the workers (long story) and GBP 5.00 for the dedicated SSL certificate). For the hosting, I use SpeedyDot - an NGINX backed (and very fast) platform. The cost of the hosting is in fact less than what I pay for Cloudflare monthly, but that's the devil I suppose.
Cloudflare enables me to leverage 165 CDN nodes across the world, and means my site typically loods in around 500ms regardless of location.
@anonymous3542 It has been some months that i tried LS cache plugin and then went back to Comet Cache.
Doing some tests today, i found several interesting things about LiteSpeed cache plugin. I have enabled both minify and combine and it seems to work fine (until now, the day is still young).
What i found ? While i have excluded some pages (wpForo one of them) from Caching, the Page optimization works (minify and combine) for even excluded pages. And that is good.
As for speed differences, i see a few more seconds added BUT by https requests for my home page for example, went from 74 to 30 (comming apparently from the combine of resources).
