Sometimes what you're looking for is not precisely performance (if so, everyone would program in pure C). While C++ gives you the benefits or C with classes, you have to do memory management and many other costly operations regarding development time and architecture design (like compiling the code).
Java/Python/C#/PHP help speed up the development (some are interpreted, have memory management, havecleaner syntax, is easier running a webserver) by losing some performance. And it isn't generally so much.
I think C++ is great you want to heavy-computing operations. Also, remember that general runtime performance remains more in algorithm complexity than language implementation.