Scalability for Dummies - Part 2: Database

• use clones to horizontally scale
• Bottleneck: MySQL database
• Solution 1:
  • Keep MySQL
  • do master-slave replication (read from slaves, write to master)
  • upgrade your master server by adding RAM, RAM and more RAM.(vertically scale)
• Solution 2:
  • denormalize
  • include no more Joins in any database query.
  • Use NoSQL. Joins will now need to be done in your application code.
  • introduce a cache.