Writing High Performance Drupal Modules

This talk is aimed at developers writing modules that have to perform well under heavy load and lots of traffic. We will present an overview of a number of techniques that we have used with success on high traffic Drupal sites. The programming techniques are straight forward; you don't need to be a rocket scientist or Einstein to write high performance code. An overview of topics we will discuss:

Basics

• Memoization
• Compsci basics

Pressflow

• Don't set session data unless necessary (mobile_tools, show varnish alternative)

Caching

• Memcache vs. Database
• Locking
• menu_callback_cache module
• General Varnish tips
• Using JS to avoid bypassing varnish cache

Queries

• Materialized views
• Master vs. slave
• Forcing Views to use slave db

Cron

• Offload cache filling

Turbo Button

• Must be pressed

Performance testing

• Testing with apache ab
• Checking varnish headers
• Devel query logging

Most of these points will be accompanied by code examples that we will talk through.