The books like 'Effective Modern C++' talk about readable and maintainable code (considering performance as well) using modern C++ but this book primarily focuses on things like: what does that code mean for processor and how to make it more efficient while maintaining the readability. All such suggestions have been supported with performance numbers. It is a huge bonus that this book also uses modern C++. Some features are yet to be included in STL but this book explained them as they were too important to skip (like Ranges library).
I loved its content on cache, lazy-evaluation, STL algorithms and reflection. The content presentation is very clear and examples have working modern C++ code.
Liked the book very much, especially as it is written about software performance from a C++ perspective (true to its title). Chapter 11 is a bonus, as it gives some insight into Boost's compute library, though the content could be elaborated a tad more. Overall, I liked the book and read through it, like a breeze (and refer to it, once in a while).