Scaling CouchDB is a relatively short book (ebook version is about 58 pages) containing performance tips, descriptions of external tools which can be used in front of CouchDB to enhance load handling, and some short code examples.
The text is terse, bordering on skeletal. This can be a plus, if you prefer something that is really CouchDB specific, but be aware that you won’t find a great deal of background on concepts like load balancing or replication, CAP theorem, etc. It would be best if the reader has some hands-on experience using CouchDB as well ( that’s probably stating the obvious, but this is not a tutorial or architecture book, and there is no gentle ramp-up to the solutions presented ).
Ubuntu is used for many of the examples, which made it easy to follow along. A minor negative with that approach, though, is that the commands used to configure software in Ubuntu (e.g., enabling Apache modules) don’t necessarily translate well to other environments. Showing the text configuration files might have been a more useful path.
Overall, densely packed information that would be useful for sysadmins planning or already involved in CouchDB deployments.