I read two of these last year and I'd recomend both, but I wanted to give my two cents on them.
The Phoenix Project: I really enjoyed reading this, but it's told as a story about fictional characters working at a fictional company, which I didn't expect. Because of the way it's written, some other people I know who read it found it a bit too fluffy. Also, from what I've heard, it's pretty much an IT focused version of The Goal by Eliyahu M. Goldratt. The Phoenix Project focused more on IT than software development, but there's also a sequel called The Unicorn Project that is supposedly more focus software development and dev ops.
An Elegant Puzzle: There's a ton of good stuff in here, but it felt a bit like reading a textbook or a white paper. Larson's writing style is really dense and dry. I found myself reading a paragraph or two and then needing to take time to digest what I had just read, which made it a really slow read.
I thought The Goal was more generally applicable. Its core idea ("theory of constraints") is described in terms of a factory floor where different workstations have different throughputs/latencies/reliability; you could apply that to a diagram of a distributed system [0], CPU [1] or server [2].
Phoenix and Unicorn project are essentially The Goal applied to software development. Reading The Goal first helped me get more out of Phoenix and Unicorn, I think. All 3 are great.
There are some excellent sequels to "The Goal", especially, "It's Not Luck," which goes on to take the theory into product and market design. It overlaps somewhat with Christensen's work on Jobs to do.
I've found lots of value in looking at all kinds of systems with this lens, though, like all things, it helps to not overdo it.
I've read The Unicorn Project. I haven't read the Phoenix one though so I can't draw comparisons, but I enjoyed it immensely because it describes how a big auto parts corporation works from different points of view. One chapter I particularly liked was more about marketing and crm than devops, although there's lots of that in there too.
Chiming in here, I love this style of book and have read the whole genre. There should be more. For someone who's just looking up from the keyboard at how to actually do things in an organization, with people, and how it all works they're absolutely thrillers and I raced through.
The Phoenix Project: I really enjoyed reading this, but it's told as a story about fictional characters working at a fictional company, which I didn't expect. Because of the way it's written, some other people I know who read it found it a bit too fluffy. Also, from what I've heard, it's pretty much an IT focused version of The Goal by Eliyahu M. Goldratt. The Phoenix Project focused more on IT than software development, but there's also a sequel called The Unicorn Project that is supposedly more focus software development and dev ops.
An Elegant Puzzle: There's a ton of good stuff in here, but it felt a bit like reading a textbook or a white paper. Larson's writing style is really dense and dry. I found myself reading a paragraph or two and then needing to take time to digest what I had just read, which made it a really slow read.