On Jan 13, 1:21 am, Stuart Sierra <the.stuart.sie...@gmail.com> wrote: > If you have > highly-optimized, custom-designed numerical algorithms written in a > low-level language like C++, you will never be able to write a version > that is equally fast in a dynamic, virtual-machine language.
I think you are essentially right (although some optimizations can only be performed with runtime information). But highly-optimized low-level code is very rigid. It is difficult to maintain it and adapt it to changing program needs and new technology (with different optimization characteristics). So I am willing to wear a certain loss of performance in exchange for a more agile program, but not too much. I think I'd be willing to wear a 20% loss in performance (perhaps even 50%), but not magnitudes much higher than this. And my gut feeling is that 20% or so should be achievable for a lisp-style language. But the Clojure+JVM solution sounds like it is still a way off from this. > Compilers are smart, but they are not that smart. I am a relative newcomer to lisp, but my impression is that lisp should be thought of as both low level and high level all in one. Ie, that the leverage from lower levels to higher ones happens primarily via macros... which the programmer has direct access to. So in theory a developer could use macros to perform compiler-style optimizations within lisp itself, except these optimizations could be tailored to the particular application. So as long as the base level lisp was implemented efficiently, the whole top-level lisp program could be efficient. But from what I can tell, even the best lisp compilers produce slow code. Even SBCL lisp seems to be 3 to 4 times slower than C++. So I must be misunderstanding something. I can't see why lisps should be inherently so slow. > That being said, experience is the only reliable guide. If you want to > know if Clojure will work for your job, the only thing to do is try > it. Yes, I think some experimental coding might be in order. But I'd like to get as much a grip on the performance landscape as I can beforehand. Thanks for tempering any over-enthusiasm and giving me your best honest assessment. Cheers, Mark P. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
