Some WordPress optimization tips

Quick tips to improve WP performances

I’ve recently had to move my company’s WordPress-based site to a new server. This gave me the chance to do some little tweaks to a 2-year-old site. I focused on optimizing WordPress, to improve site’s performance while decreasing CPU and server load. Since I was able to reduce the load time of my company’s site significantly (I used YSlow to monitor performances), I thought to share the steps I followed, as I feel this might be helpful.

1. Install WP Super Cache plugin

You can download the plugin here – it’s pretty easy to setup.
The plugin itself does 80% of the work and helps a lot speeding up load times.

2. Add some .htaccess rules to force caching of static elements, such as css, javascripts and images.
I had the chance to attend to Fullo’s speech about WP optimization at last year’s WordCamp Italy, when he shared some really useful tips that I finally put into practice. He has posted the slides to his blog, with code snippets.

<IfModule mod_expires.c>
ExpiresActive On
ExpiresDefault "access plus 1 seconds"
ExpiresByType text/html "access plus 1 seconds"
ExpiresByType image/gif "access plus 2592000 seconds"
ExpiresByType image/jpeg "access plus 2592000 seconds"
ExpiresByType image/png "access plus 2592000 seconds"
ExpiresByType text/css "access plus 604800 seconds"
ExpiresByType text/javascript "access plus 216000 seconds"
ExpiresByType application/x-javascript "access plus 216000 seconds"
</IfModule>

<IfModule mod_headers.c>
<FilesMatch "\\.(ico|pdf|flv|jpg|jpeg|png|gif|swf)$">
Header set Cache-Control "max-age=2592000, public"
</FilesMatch>
<FilesMatch "\\.(css)$">
Header set Cache-Control "max-age=604800, public"
</FilesMatch>
<FilesMatch "\\.(js)$">
Header set Cache-Control "max-age=216000, public"
</FilesMatch>
</IfModule>

3. Add some .htaccess rules to enable compression of Html pages

This trick was suggested by my friend Luca, who also sent me the following code:

# compress all text & html:
AddOutputFilterByType DEFLATE text/html text/plain text/xml

# Or, compress certain file types by extension:
<Files *.css>
SetOutputFilter DEFLATE
</Files>
<Files *.js>
SetOutputFilter DEFLATE
</Files>

4. Finally, add a robots.txt file to prevent unnecessary bot traffic

This was also suggested by Fullo’s priceless slides:

User-agent: *
Disallow: /cgi-bin
Disallow: /wp-admin
Disallow: /wp-includes
Disallow: /wp-content

User-agent: Mediapartners-Google
Allow: /

User-agent: Adsbot-Google
Allow: /

User-agent: Googlebot-Image
Allow: /

User-agent: Googlebot-Mobile
Allow: /

User-agent: ia_archiver-web.archive.org
Disallow: /

Before leaving you, here are some other useful articles I’ve found while googling around:

• WordPress Codex › WordPress Optimization
• WordPress Optimization Bible
• Optimizing WordPress Servers