Book Review: Java Performance: Charlie Hunt, Binu John

My Rating:  5 out of 5 stars.  (Strong Buy)

Why you need to buy this book?
1) There is no other strong book on Java Performance in the market.
2) Written by experts who deal with improving the performance of the Hotspot Java VM, on a daily basis.
3) Extensive description on the internals of the Hotspot JVM. Previously the JVM was a blackbox that would run your Java applications. This book will lay out the JVM as an open book. So you have an opportunity to master the JVM.
4) It is from Addison Wesley who publish GREAT books.

My Favorite Chapters:
Chapter 3: JVM Overview.
Chapter 4: JVM Performance Monitoring
Chapter 5: Tuning the JVM, Step by Step

 Review:
I have had this book for a month now.  But I have not read it completely. The reason is that this is an advanced topic.  The book goes into deep lengths to describe the Hotspot JVM concepts that you have to tread very slowly.  I mean very very slowly.

My approach has been to go to the chapters which I am interested in.  Then go back to the chapters that give background information. I strongly recommend that you keep this book close to your work area, because you will require it often, to not only brush up on your reading but also to use it as a reference, when you tune your Java applications. BUT THIS BOOK IS A DEFINITE MUST FOR YOUR COLLECTION.

Let us go chapter by chapter on the ones I have read.

Chapter 2: Operating System Performance Monitoring
I particularly liked the treatment on “monitoring CPU utilization” on various operating systems (windows, linux etc).
There is a lot of information on Memory Usage Monitoring, Disk IO Monitoring that a performance engineer will definitely need.

Chapter 3: JVM Overview
This is a brilliantly written chapter.
Right at the start, the authors state that the users of Java technology see the JVM as a blackbox. My opinion : Well, this is the irony or fact or destiny or whatever. Java Performance has been voodoo over the years. Extensive documentation (that is not confusing) along with reasonable JVM defaults, is the way to go.

The chapter does very well to talk about the ordinary object pointers (OOPS) and the new JDK6+ feature called “compressed oops” to get 32bit like performance on 64bit JVMs. The gist is that compressed oops feature will improve the cpu cache utilization.

The chapter goes into great length to talk about class loading, internal VM architecture etc.  A very very good chapter. Read the section on Garbage collection. There is great discussion on the generations as well as on collectors etc.

Chapter 7: Tuning the JVM step by step

This chapter is just a beauty. There is around 70 pages devoted to this chapter.  So much content just for JVM tuning.  Probably, this topic requires a 1000 pages. But the authors have done the JVM tuning as part of their jobs. So they have condensed the topic in to 70 pages based on their years of experience.

I will update this review as I finish reading the other chapters. I can grumble that the book is very intense but it is a happy grumbling.

Final Commentary:
I have attended talks by Charlie Hunt over the years.  Charlie is extremely knowledgeable and is very passionate about the JVM. No wonder, he has turned up a gem of a book.

Anil Saldhana
JBoss Community
Chicago Java Users Group

Java Performance on Multi-core Platforms By Hunt, Charles J./ Hohensee, Paul/ John, Binu/ Dagastine, David (Google Affiliate Ad)

Book Review: OpenAM by Indira Thangaswamy

Title: OpenAM
Author: Indira Thangaswamy
Publisher: Packt Publishing (January 25, 2011)
ISBN-10: 1849510229
ISBN-13: 978-1849510226

Link on Amazon: http://www.amazon.com/OpenAM-Indira-Thangasamy/dp/1849510229

My Rating: Buy


General Comments
Books on security projects are quite rare. It is also quite difficult to fully document the breadth of possibilities with Open Source Software. Toward this, I commend Indira’s efforts at writing a book on an open source product, OpenAM. Over the years, I have seen Indira answer user questions on the openam/opensso user forums. So he does know a lot about it. Writing books is not a joke. In the preface, Indira just hint at the pain he took in writing the book. Books take away quality family time. Kudos to Indira.


Detailed Review
Indira has done a fine job with the book. He has clearly divided the content into 3 areas. The first area that occupies the first few chapters are completely devoted to what OpenAM is, what problems that it solve and where do you get it from. Then the next few chapters that occupy the bulk of the book are devoted to HOW YOU do things with OpenAM. Finally, he closes the book with Troubleshooting and Diagnostics.

The first chapter begins quite well with a description of why Identity and Access Management (IAM) is required in the industry. The short example of the FBI breach in the early 2001 highlights the need for proper entitlement management. After an introduction of benefits of IAM, Indira moves on to the history of OpenAM starting its roots at Sun Microsystems in 2000. This is good for obtaining an historic perspective on OpenAM. The OpenSSO architecture diagram is valuable to users who want to grasp the elements of the software packaged in OpenAM.
The section on “what kind of problems does OpenSSO solve?” describes at an high level the features OpenSSO provides: Access Management, Federation, Securing Web Services and Entitlements. I particularly liked the table at the end of this section that gives a graphical description.

In the second chapter, Indira talks about configuring opensso on Tomcat. He also shows how to configure OpenSSO using the console.

The third chapter is all about administration. We see snapshots of the console as well as some CLI interactions to configure. I think the section on customizing the console with user schema needs some additional work (with examples of course).

I liked the fourth chapter that describes the various types of authentication as well as session services. The authentication types (Module, Level, Service etc) have been sufficiently described. If the reader is interested further, hopefully he can get additional information from the project guides.

Chapter 7 was decent with integration with salesforce and google apps. This chapter basically empowers the user to use SAAS based apps with OpenAM as the IDP. The console snapshots should be sufficient for the reader to get it to work. Since I did not try it out, I am not 100% whether this chapter needs additional work.


Suggestions for improvement
* Indira shows how to configure things with the console as well as the command line interface. You should try to add warning boxes in the book stating which settings need the CLI.
* I am not sure if the reader is able to obtain the ldap schema for various ldap servers. Or the openam console does it for you automatically. Please clarify in the book.
* In the administration of OpenAM, things can go wrong. There is very little information on what things need to be watched out, while administering the product. Showing console snapshots or CLI is not sufficient to administer. Please describe what the CLI parameters are.

Disclaimer: I am not endorsing the product OpenAM. All I am doing is reviewing a book on an open source project. I need to play around with OpenAM/OpenSSO such that Project PicketLink is interoperable with it.