WordPress Optimization – code hacks

For the fun and profit, I’m trying to improve (and speed-up) my WordPress blog. Beyond WP Super Cache I mean 😉

Because a browser (Internet Explorer, Firefox) can only make a limited number of HTTP requests simultaneous to a DNS host name, I added some to my website: img., css. and js. The plan is to load CSS files from css.mysite.tld and images from img.mysite.tld, you get the idea.

I have virtually no knowledge of the WordPress API, but for as far as I tried, this is a pain to do. Because you have to code-change every plug-in. For example:

* my Journalist theme: I added to functions.php:

add_filter('stylesheet_uri', 'change_css');
function change_css() { return "http://css.saotn.nl/wp-content/themes/journalist/style.css"; }

Unfortunately this does not work for added plug-ins, since bloginfo('stylesheet_url') is only for the current theme.

* One of the other changes I had to make was in one of my plug-ins “Secure and Accessible PHP Contact Form”:

get_bloginfo('wpurl')

became

str_replace("saotn.nl", "js.saotn.nl", get_bloginfo('wpurl'))

(I know, my PHP skills aren’t that good).

* And in WP-Syntax:

$css_url = str_replace("saotn.nl", "css.saotn.nl",WP_PLUGIN_URL).'/'.str_replace(basename( __FILE__),"",plugin_basename(__FILE__));

Is there a better way, with less code changes, to reduce HTTP requests? A general “CSS/JS URL Setting” in WordPress’ back-end would be nice 🙂