BuddyPress.org

It ought to be fine, and no doubt you’ll be able to keep an eye on how things are performing as the level of activity on your site scales up.

If you mean “comments” as in “comments on a blog post”, that’s obviously part of WordPress. That will definitely scale fine.

If you meant “comments or replies on activity stream items, or status updates”, that’s BuddyPress. This should scale just fine, too.

This assumes your server(s) configuration is optimal, and that you haven’t got any slow code running in other plugins/custom code, or in your theme. I/we can’t really help you with that here — running a performant server(s) for WordPress is outside the scope of providing BuddyPress supports.

The only piece of hosting advice that I’d recommend for any WordPress-powered site, but especially larger sites, is to make sure you’re using an object cache, such as memcached.

@harry4039 – Another useful bit of information for you:

Wordpress.com runs on WP-Engine, which is where we are now hosting our membership/lms/e-commerce WordPress site, and we have seen massive improvements in speed at their premium levels.

It is important to note that the level of concurrent users you’re talking about requires serious server scaling, especially when those users have profiles and are interacting constantly. The premium levels at WP-Engine start at $600 a month and go up from there, but since we have an extremely active user base, the non-profit I’m working with is going for it.

The support has been phenomenal, and while we still have some slow action on the backend at times, the front-end is more than twice as fast.

Also, we use Disqus for comments, which also greatly reduces server load since Disqus handles all the comment parsing and data flow. Unfortunately, their theming and customization options are seriously lacking (you can choose light or dark theme, woohoo!).

I’m really into testing the limits of WP and BP right now, and so far they handle well, though lots of development, fixes and customization are needed on a regular basis due to updates and bugs on a big stack of plugins. Good luck with yours!

~AA~

Footnote: I do not work with, nor am I associated with WP-Engine or Disqus in any way. 😉 In fact, I host most of my smaller sites on Dreamhost, and have generally thought $1K per month for hosting to be outrageous before now.

@harry4039 – Sorry to hear about that. I’m sure the client scale makes a difference. I’ll admit, they have made a few mistakes with us as well, but respond quickly and have generally been good in the support department. How do you like Linode?

And yes, Disqus is not ideal if you’re trying to address every commenting location.

EDIT: Also just discovered Linode is an infrastructure partner of WP-Engine. Looks like they are more of the raw hosting and less of the wp-optimization services, which is the specialization of WP-Engine.

I’ve found the most important quality you should look for in a hosting company is support. A host that offers good support and is accommodating to your needs is worth a million bucks (my own personal opinion and from experience).

As @djpaul mentioned earlier, the terminology is important because ‘comments’ can refer to 2 things:

• post comments
• activity comments.

Post comments are handled by WordPress and are stored in the wp_comments database table (see here). Activity comments are handled by BuddyPress and are stored in a custom table created by BP called bp_activity (see here).

Post comments definitely scale. Personally, I’ve not had experience with a site that receives a massive amount of activity comments but as @djpaul points out, these should scale just fine too.