Overall, Rust is pretty good for performance. Write the most simple stuff, and it will usually run within a factor of two from optimized C/C++ code. However, Rust makes some tradeoffs for different reasons than sheer speed, so here’s a handy list of some things that may bite you and how you can speed them up.
Article: Rust Performance Pitfalls — Llogiq on stuff
HN Discussion: Rust Performance Pitfalls | Hacker News