High Perfomance
a guide for optimizing the performance
of Joomla! websites
by Fotis Evangelou (JoomlaWorks)
www.joomlaworks.gr
Joomla!Days Netherlands - 12 & 13 June 2009

What's covered in this session
• Basic principles of web content delivery
• Prepare Joomla! for prime time
• Optimize our template and our content
• Configure hosting
www.joomlaworks.gr

Basic principles of web content delivery
The closer the server is to the user, the better
- DNS lookups (avoid redirects)
- The concept of the CDN (Content Delivery Network)
Browsers use 2 HTTP connections per domain to
download content
- Increase website download time using subdomains/CDN
- Combine CSS files
- Combine Javascript files
- Combine layout images into sprites
All modern browsers accept compressed content sent
from the server
- Compress HTML, CSS and Javascript code
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Prepare Joomla! for prime time
Prepare the tools for your work
- Install Firefox with Firebug, YSlow and Web Developer Toolbar
Global Configuration
- Enable Joomla!'s built-in cache mechanism
- Enable GZIP
Extensions
- Choose extensions that properly separate content from
layout/behaviour – disable their CSS/JS includes and call CSS/JS
code into your template where possible.
- Enable caching for modules
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Optimize our template and our content
- Combine and compress - using Gzip - CSS/JS files
- Do not pack your JS code, feel free to minify
- Use one JS library/framework
- Initiate JS code into as little onload events as possible
- Put all your layout (non-content) images as background images in
your template's CSS file
- Combine all your layout non-repeating images into one big image
(sprite), use CSS positioning to display
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Optimize our template and our content
- Resize/resample content images manually or use a plugin to do
that
- Understand when to use GIF, PNG or JPEG
- Enable debug in Joomla!, check the number of queries with
cache on and off. Identify slow queries in PHP code.
- Dynamically replace URLs to point to subdomains/CDN
(make site.com/images/ show up as images.site.com)
www.joomlaworks.gr

Configure hosting
- Optimize MySQL depending on your needs and taget audience
- Use a CDN for image, CSS, JS and other static content delivery
- Split website load into 2 servers (if possible): one acts as web
server, the other as database server
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Case study: gazzetta.gr
www.joomlaworks.gr

Thank you
www.joomlaworks.gr