PostgreSQL High Availability Cookbook - Second Edition

Introduction

Abstraction can protect a database from even the busiest platform. At the time of writing this book, applications and web services often involve hundreds of servers. If we follow a simple and naïve development cycle where applications have direct access to the database, each of these servers may require dozens of connections per program, even with a small server pool that can result in hundreds or thousands of direct connections to the database.

Is this what we want? Consider the scenario illustrated in the following diagram:

We need a way to avoid overwhelming the database with the needs of too many clients. As we suggested in ...