The Art of Capacity Planning
This week I opened a beautiful package from O’Reilly. It contained John Allspaw’s new book, The Art of Capacity Planning. As you can see, the cover is a delight to look at. But you shouldn’t judge a book by it’s cover! Luckily, what’s inside the book is also a delight.
Now, let me make a disclaimer. I know John. We first crossed paths at Yahoo!, and have worked together on some side projects, most notably the Velocity conference. I know he’s an expert in the area of capacity planning. I know he’s highly regarded by other leaders in the operations space. I’ve heard him speak at conferences, brainstorm in small group discussions, and share his experiences with others. Given this background, I expected a book full of lessons learned, practical advice, and real world takeaways. Thankfully, for all of us readers, The Art of Capacity Planning delivers all of this and more.
Right out of the gate, John covers a topic near and dear to my heart: metrics. His advice? “Measure, measure, measure.” John reinforces this by including an incredible number of charts throughout the book. He goes on to say that our measurement tools need to provide an easy way to:
- Record and store data over time
- Build custom metrics
- Compare metrics from various sources
- Import and export metrics
As I read the book, I found myself nodding and thinking, “yes, yes, this is exactly what I learned!” Although it’s been more than five years since I was buildmaster for My Yahoo!, I really resonated with the advice John provides, like this one: “Homogenize hardware to halt headaches”. (You have to love the alliteration, too.)
In a thin book that’s easy to read, John covers a large number of topics. He talks about load testing, with pointers to tools like Httperf and Siege. There are several sections that talk about caching architectures and the use of Squid. He provides guidelines when it comes to deployment, such as making all changes happen in one place, the importance of defining roles and services, and ensuring new servers start working automatically. At the end he even manages to cover virtualization and cloud computing, and how they come into play during capacity planning.
The Art of Capacity Planning is full of sage advice from a seasoned veteran, like this one: “The moral of this little story? When faced with the question of capacity, try to ignore those urges to make existing gear faster, and focus instead on the topic at hand: finding out what you need, and when.” When I read a technical book, I’m really looking for takeaways. That’s why I loved The Art of Capacity Planning, and I think you will, too.