Optimizing your LAMP stack for Drupal (DrupalCon 2009 notes)

Performance and Scalability: Optimizing your LAMP stack for Drupal
Eric Mandel

Performance

• different things to different people
• amount of useful work accomplished by system, compared to resources used
• however you define the atomic unit of measurement -- that one thing -- it's generally how fast can you do it.
  • in a web app, how fast can you serve something (a page) to a user?

Scalability

• Can the system grow without degradation
• How big is the system and how big can you make it?
  • In a web app, how many users can your app serve while maintaining acceptable performance levels?

Performance: 1 user, Scalability: manu users

Drupal's Performance Problems

• Lots of queries
• Unoptimized queries
• search gets slower as nodes increase
• 3rd party modules are performance unknowns
• logged-in users require more queries
• handling millions of nodes requires hacking core

[Damn... just lost my notes here...]

Scalability Prerequisites (cont.)

• Isolate multimedia files
• Use a CDN or have a plan to use a CDN