Following on from Faster WordPress, which went up on Shout a couple of weeks ago, this post explores how to optimise WordPress for high traffic. We’ll take high traffic in a small blog context — 1,000 or so visits in a day, but exactly the same techniques apply to much larger traffic blogs.

The average WordPress theme isn’t optimised. Whilst it may claim to be or may in fact be to an extent, the nature of WordPress themes means they have to be able to fit in any situation and so they are never going to be as well optimised as a theme which has been designed specifically for a single purpose. I’m not saying don’t use an off-the-shelf theme, just you’ll need to customise it in order to get the best performance out of it.

As we go through this post, the methods we’re going to use will get increasingly complicated — start with the first and go as far as you can!

Get a good host

You can do all the optimisation you like, but if your hosting isn’t up to scratch, it’ll have absolutely no use. Avoid over subscribed shared plans on the likes of GoDaddy and HostGator and get a plan that suits the level of traffic you’re likely to get. WPShout is hosted by WPWebHost and is on the equivalent of the Buddy Plan but is still on a server with 164 other sites — something far from ideal. I would, however, recommend WPWebHost. The support is on the whole good and, more importantly, the site stays up the vast majority of the time.

You can see which other sites are on your server with this tool.

Use a caching plugin

I can’t recommend W3 Total Cache enough. Whilst there are other caching plugins are available and they all have their own pros and cons, W3 Total Cache has a couple of extra features like support for a CDN and auto-minifying which make it invaluable. It is worth noting, though, that unless you set it up correctly it will have little or no effect and may even slow your blog down, as this post shows!

Things like the ability to minify and compress your HTML just by turning on the setting are great to have. Have a look at WPShout’s source and see for yourself!

As I mentioned last time, running a CDN is vital and WPShout runs on WPCDN — a service a can thoroughly recommend. Mark Bailey from WPCDN explains the advantages:

A CDN can increase a website’s performance by serving items from the closest possible location to the visitor. The web server would still provide the pages, but images and other larger items would be served from the CDN.

–Mark Bailey, WPCDN

If you, understandably, don’t want to pay for something which isn’t essential for your blog’s existence, have a look at the Free CDN plugin. I’ve no idea what speed boost it’ll give you, if any, so make sure you compare it with your blog’s current loading time.

Get rid of unnecessary plugins

Plugins which have extra Javascript files are a pain because they have a direct impact on the load time of every single page. Whilst you could do what I’ve done on Shout and manually combine the files and then remove the function that adds the JS in the plugin, you could just ask yourself whether you really need the plugin. Michael Martin from ProBlogDesign is currently redesigning PBD and had this to say:

The big thing with WordPress is working out what plugins you really need, and which actually aren’t worth the extra load times.

–Michael Martin

And he’s right! Do you really need a widget on your sidebar that shows the timezone in Australia? Review your plugins and only keep the ones you really need.

Experiment!

Experimentation is the way forward. Try out various combinations or plugins, caching, getting rid of things and the like and you should be able to find something that works for you. Good luck!