The Performance of Open Source Applications (aosabook.org)

Index is on http://aosabook.org/en/

It's also important to note that, while you can get the book for free, most of the profit goes to Amnesty International when you buy it[0].

[0]: http://aosabook.org/en/buy.html

Let us know when the epub version is up on the store, would love to have this all in one place. Already got the other 2 books.

That site is so performance-oriented it took me 2 minutes to find the link to the book.