Quite often I have people asking whether or not WordPress can handle their large site. They have very genuine concerns that WordPress can not handle things like scaling and caching and large visitor loads.
Whether you are performing due diligence or just wondering what WordPress can do, the below should be quite useful to you.
Its always best to lead by example right! So here we go!
A whole bunch of sites with massive user bases use WordPress. Here are a few-
http://tutsplus.com/ – A HUUUGE site with thousands of articles, media and users. Alexa rank 591
http://freelanceswitch.com/ – I use this site a lot! Both the site and the jobs board are powered by WordPress. Alexa rank 5,813
http://mac.appstorm.net/ – Another site with a huge following. Alexa rank 5,856
http://wiki.envato.com/ – The wiki for the ginormous envato market place. Alexa rank 4,101
http://workawesome.com/ – A blog but a large blog nonetheless. Alexa rank 31, 945
http://blog.themeforest.net/ – The blog for themeforest, possibly the largest template site on the net. A huge following. Alexa rank 287
With large sites caching is very important. Querying the database as few times as possible and only doing so when cached content is not available is crutial for a large site. Serving users static html rather than server intensive php powered by goodness knows how many DB queries saves a tonne in terms of server resources and site responsiveness. WordPress already has numerous plugins for this. The best two are WP Super Cache and W3 Total Cache.
http://codex.wordpress.org/High_Traffic_Tips_For_WordPress is a really good read straight from the WordPress mouth about the capabilities of WordPress. For me, the overriding message from that page is that it is more about the hardware behind the site than the software serving the site.
37 signals (the makers of Basecamp and other very successful web apps) wrote this very honest and wise piece.
Basecamp is probably the most successful online project management tool out there and they openly admit that precious time is lost worrying about problems that may never occur. And when they do occur it is optimal to fix them and tweak the set up as they happen.
As they say -
In the beginning, make building a solid core product your priority instead of obsessing over scalability and server farms. Create a great app and then worry about what to do once it’s wildly successful. Otherwise you may waste energy, time, and money fixating on something that never even happens.
Another brilliantly honest article from the same guys-
Edublogs is one of the most successful education based blogging platforms and they use WordPress MU (multi-user). Here is an in depth (and quite geeky) article on the set up of that system.
Matt Mullenweg, the founder of WordPress made an interesting response to somebody moving their site to drupal from WordPress after getting to 200,000 hits per day. He offers some sound advice-
“Barry” is the “Chief Systems Wrangler” at automattic (the people behind wordpress, askimet, vaultpress and IntenseDebate) and he wrote this article about hyperDB -
Essentially what he is saying is that using hyperDB (found here http://wordpress.org/extend/plugins/hyperdb/) enables huge sites to effectively and sparingly use DB queries to further optimise a high traffic volume and user interaction site. Read more from “Barry” on scaling here http://barry.wordpress.com/category/scaling/
The only other thing I will add is that words like “blog”, “theme” and “plugin” are used a lot with WordPress. Do not be put off by them! WordPress started out life as a blogging platform and it has struggled to shift that association. In truth, WordPress is actually an extremely powerful Content Management System with a highly intuitive and extensive API. Plugins are essentially little (or large) packages that add extra functionality to a WordPress install. Themes define the look of your site. They contain all the client side code and it is in themes that a design of a site is held.