Performance and its cousin Scalability are always an important part of any software architecture and while some cynics will say some of the tips in this book are common sense, there's plenty of really good advice that if adhered to they would certaintly lower the probability of scalability issues which are nearly inevitable at some stage in the life of a project.
Among my favourites tips:
- Put Object caches on their own tier. This makes it easier to size their hardware needs - object caches typically need a lot of memory.
- Pass on multi-phase commits if possible as they are difficult to scale.
- Smart reminders when it is really important to use aschronous models (integrating with 3PP frameworks, when there is a temporal constraint).
In summary, there are not too many good books on software architecture and this is certainly one of the best I have read. I have already read parts of it 3 times and I am sure I will be referring to parts of it again.