Book Image

PostgreSQL 9 High Availability Cookbook

By : Shaun Thomas
Book Image

PostgreSQL 9 High Availability Cookbook

By: Shaun Thomas

Overview of this book

A comprehensive series of dependable recipes to design, build, and implement a PostgreSQL server architecture free of common pitfalls that can operate for years to come. Each chapter is packed with instructions and examples to simplify even highly complex database operations. If you are a PostgreSQL DBA working on Linux systems who want a database that never gives up, this book is for you. If you've ever experienced a database outage, restored from a backup, spent hours trying to repair a malfunctioning cluster, or simply want to guarantee system stability, this book is definitely for you.
Table of Contents (12 chapters)
11
Index

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 the previous chapter, a PostgreSQL server experiences its best performance when the amount of active connections is less than three times the available CPU count. With a thousand incoming client connections, we will need hundreds of CPU cores to satisfy the formula.

Every incoming connection requires resources such as memory for query calculations and results...