These days, we find a lot of books on Oracle Technology flooding the market in tandem with the product announcements. Most of the books just rehash the standard (or even beta) documentation, or published metalink notes. This book is certainly does not belong to that category.
First of all, I find that this is the first book which tries to present an accurate picture of RAC. This book clearly demonstrates that RAC is the improved version of OPS and shows the evoluation path of OPS to RAC. I suppose most of the people who have worked on Oracle for a long time will agree with that statement. Most of the current books in the market that I get to read just tend to follow what Oracle marketing says, that RAC is not OPS.
Notably, this is the first ever book on RAC, that has shown me how cache fusion really works. Cache fusion is the secret of RAC and not many people knows how they work under the hood. In this book the author has clearly demonstrated how the resources are mastered, how the locks are coverted and that a row level locks (transaction locks) are different to a buffer locks (Global Cache locks). There are places where the author has used block dumps to explain the internal implementations.
What I see is that the author has tried his best to concentrate on concepts and inner workings of various things inside RAC.
In that sense, this book is well stocked with lengthy discussions for the RAC hungry technicians. the book requires a lot of attention (and sometimes repeated readings) and certainly this is not bed time reading!
The beginning is light and interesting, especially the history of OPS which is difficult to find and collate.I really enjoyed reading the Global Resource Directory chapter along with the Cache Fusion. Many other chapters are worth a mention including the Backup and Recovery, Performance Tuning (No wonder,the author has another best selling oracle performance tuning book!) and Application Development. The consistency and approach is great and the author has tried to keep things in context, most of the times. The author has managed to touch many topics in RAC though some of them could have been lengthier and more conclusive.
One last thing, If you want to buy a book just to get the bunch of day to day commands for RAC and plan to work on RAC, please do not buy this book. You will be thoroughly disappointed as this book doesn't belong to that category. It only tells us how things works internally, what are the concepts behind the scenes and not the magic commands to administer RAC.
As a whole, I find this book a very enriching reference/concepts book to read when I don't know how something works in RAC. If there is a secret in RAC, there is a good chance you might find it in this book rather than any other. Contents in this book are generally not seen in other RAC books that I have read and the quality of presentation is much better.
Good buy but prepare for some heavy reading.!! I recommend this book to every DBA (even architects) who want to know HOW RAC works.