I do molecular dynamics simulations using LAMMPS on HPC systems. LAMMPS is written in C++. I'm not normally a fan of object-oriented languages, but this seems to work well for a system where you have an abstract base class (like an atomic pairwise potential) that allows users to easily derive their own potential class from it.
I wouldn't say LAMMPS is super-optimized for a particular application compared to some other MD codes, but it is very good for a wide-variety of situations, kind of like C++. Just guessing, I'd say LAMMPS is easily within a factor of 2-3x of most hand-tuned assembly codes, but the generality of it really outweighs the performance penalty.
Personally, in terms of programming languages, Julia is really growing on me. I've been using it for performance-intensive, single-threaded programs and it works great. I'm actually considering experimenting with it for some of my web application projects (currently using Node.js for those) just because of how much I like the language design.
I wouldn't say LAMMPS is super-optimized for a particular application compared to some other MD codes, but it is very good for a wide-variety of situations, kind of like C++. Just guessing, I'd say LAMMPS is easily within a factor of 2-3x of most hand-tuned assembly codes, but the generality of it really outweighs the performance penalty.
Personally, in terms of programming languages, Julia is really growing on me. I've been using it for performance-intensive, single-threaded programs and it works great. I'm actually considering experimenting with it for some of my web application projects (currently using Node.js for those) just because of how much I like the language design.