Yes, probably by a factor of 2-10x in most situations. Also memory footprint is going to be far lower too, so cheaper servers/leasing of resources. It's great for webapps (or restful backends) on embedded systems in particular. As always though I've seen people far more likely to be bottlenecked on I/O and database requests than on raw computing power. Usually even python and ruby are waiting on something else :) . Amdahl's Law is always worth keeping in mind.

Generally. As always, devil is in the details. Rust usually has a very similar performance profile to C and C++.

The memory usage part is where Rust is clearly at a stark advantage in that comparison.