Re: Why are intepreters so slow today

Eythan Weg (
Mon, 18 Apr 1994 19:15:59 GMT (Seth Breidbart) writes:

>In article <>, John Nagle <> wrote:
>> Lately, I've been looking at interpreters suitable for use as
>>extension languages in a control application. I need something that
>>can do computation reasonably fast, say no worse than 1/10 of the
>>speed of compiled C code. Interpreters have been written in that speed
>>range quite often in the past. But when I try a few of the interpreters
>>available on the Mac, performance is terrible.
>> My basic test is to run something equivalent to
>> int i; double x = 0.0;
>> for (i = 0; i < 1000000; i++) x = x + 1.0;
>>The Smalltalk and Python versions are slower than the C version by factors
>>of greater than 1000. This is excessive. LISP interpreters do a bit
>>better, but still don't reach 1/10 of C. What interpreters do a decent
>>job on computation?

>Have you tried APL? I don't have a mac, but an equivalent expression
>(using APL properly, +/1000000 .rho 1.0 ) should run at least as fast
>as compiled C.

I think this answer is not pertinent. When you have to loop
unconditionally you may want to do this (in J) like

>: ^: 1000000 (0)

which is equivalent to the C expression. As for speed, check it
yourself. You will be surprised.