WP Super Cache is one of the top caching plugins for WordPress out there. In fact, it’s been downloaded more than 2 million times! (Not sure what blog caching is? Check out this post before you proceed!)

And the volume of installations are definitely an indication of it’s success in doing what most people need and that’s why I recommending it as a caching plugin for many clients and bloggers.

In fact, I use it for many of the properties that I actively manage! Here are a few:

Standard Theme WordPress Theme Demo
TentBlogger WordPress Themes Demo
State of the 8 Blog
And many more! Those are just a few that have been optimized for use of the plugin. This includes the WordPress Theme itself, plugins, server/hosting setup, and especially the WP Super Cache plugin itself.

As a result I highly recommend that you take a look at installing this for most (if not all) blogs – and it’s definitely essential to include as an option (of the many WordPress caching options) as you do your research for the right caching plugin!

So, what is it going to take? You see, 99% (or more) of self-hosted WordPress blogs run on an Apache + PHP-based web server configuration. I believe that to completely tweak-out a WordPress blog with W3TC you need either a NGINX + FastCGI configuration or a custom Litespeed + Op-Code in production (I personally run this setup with APC – Alternative PHP Cache). If you have no idea what I’m talking about then I think it’s only fair that one shouldn’t expect to get max and/or superior results unless they have one of those configurations or if you’re a kick butt at engineering an Apache-based environment.

This doesn’t even factor in one of the biggest contributing factors to this plugins’ success which is your blog’s hosting provider! A shared environment will always produce lower results than a virtual, semi-virtual, or dedicated system. In many circumstances you won’t be able to max this plugin out on a shared environment due to the host’s software installation and configuration constraints!

Finally, there are many other options within the plugin like using a Content Delivery Network (CDN) that further enhance the value of W3TC, even though adding a CDN is not a unique value proposition (WP Super Cache has this too). Some of these options, like a CDN, require not only additional technical ability but also money which most bloggers, especially new ones, simply can’t afford. This puts the optimal usage of W3TC even further away from the average blogger.

Of course, you could say the same thing about most of the caching plugins out there that “max” results require server-side engineering and scripting to pump out the best results!

In any case I typically recommend that most bloggers head back over to WP Super Cache as their caching plugin of choice since most server and hosting providers can natively provide an optimal return on a very simple installation.

There are a lot of places, where you need client's IP address in Drupal (or any other CMS/web app of course). The problem arises, when you use a reverse proxy server (like Varnish), since every request to web server will be done by the latter. We will have every single visitor of our website coming from a single IP (reverse proxy), as a result.

Drupal is smart enough to overcome that. Reverse proxy servers can be configured to forward original client IP in a request header (usually X-Forwarded-For). This value can be used on web server to know where our visitory come from. In Drupal we have function ip_address(), which will read and return client's IP. If we take a look at this function's code, we can see that it already has support for situations, where reverse proxy is used. This function will still return Varnish's IP address by default, though.

En artikel om hur man enkelt bygger en cachefunktion för all output från ett PHP-script.