Java Performance: The Definitive Guide: Getting the Most Out of Your Code

Overall a very good book. Definitely worth a read!It seems to focus primarily on the Hotspot virtual machine. With other VM implementations now available, for example Eclipse OpenJ9. It would be good to see an acknowledgment to these are well.

I liked the first part of the book, around JDK internals, especially the explanation around various GCs.Now I did not like programming advices, to me many seem non-sensical. Even in the provided examples the author usually returns class implementations instead of APIs which is a very bad practice, and in the JPA looks like there's bullshit (especially around the cartesian issue w/ Hibernate). But the good advice in the second part is "tune your code before tuning the JVM", which is basic common sense.

This book is just amazing for all the programming enthusiasts. Books like these aren't particular to a certain language. Instead, they can give you references and best programming practices in general too! Without a second thought, go for this book.

I've been working with Java for over a decade and have read many many books on the topic. This is the first book I read that really goes deep into the details of the performance of both the language and the JVM. Not only does it explain why, the book also includes proofs for it's claims. I definitely learned quite a bit from this book even after reading more books than I can count and working in Java since version 1.0.2.

It explains all kinds of tunings that can be done to the JVM. Many of them I didn't know myself. Absolutely a must for any Java developer, systems engineer or Java Project Manager.