Typically, optimized Lisp code is around 50% slower than C. This is only available on mainstream processors. Specialized and very fast hardware usually lacks Li

Typically, optimized Lisp code is around 50% slower than C. This is only available on mainstream processors. Specialized and very fast hardware usually lacks Lisp implementations - with a few exceptions. Which puts it into similar regions as Java, Go or D. Unoptimized Lisp code can be a lot slower, but it then supports a bunch of interesting dynamic behavior. The main approach of better performing Lisp systems is to provide a wide variety of programming styles and a lot of flexibility, while being at the same time fast enough, so that not much software needs to be written in C or assembler. For example in a large CAD system it is possible to write much of the code in Lisp - in a space where such an application has to compete with systems written in C and especially C++. Depending on the quality of the Lisp implementation, the C/C++ part gets larger or smaller. For example one of PTC's Creo CAD systems is written mostly in Lisp - a bit more than 6 million lines of Lisp code was reported a few years back.