Possibly, that's the most hardcore technical book I've ever read. In times of abstractions, when all things are distributed and it's almost impossible to find where your app is running Brendan Gregg has reinvented his own wheel. He's doing what most engineers are dreaming of doing but neither they have time nor interest from their stakeholders. He's getting to the bottom of what comprises the performance.
Screw your Dockers and Prometheuses, with the few exceptions of few self-written scripts and eBPF one-liners the author is using common tools to measure and troubleshoot the performance problems. This book doesn't go too far as trying to solve all issues with GNU utils only, but almost every tool described in the book is battle-tested and has earned its fame long before this book. Gee, it has full chapters on sar & perf.
Whoa, this book is a refresher in the world of abstractions that we live in now. Not sure, how practical this book is for anyone outside of Netflix but nevertheless it's 100% worth your time if you're interested in how things are working under the hood.
My score 4/5