Introduction

1. What This Module Covers

The storage module scaled the database. The caching module took the read pressure off it. This module scales everything else. That means the application servers and the traffic between them. It also means the machinery that decides how many servers should exist at 3 AM versus 3 PM.

This module also gives the full answer to the last of the five questions: how does it grow? The answer starts with a correction. "Scaling" is less dramatic than it sounds