Yes, that indeed seems to be the problem. However, even after managing to
wrap the types properly, using `divides?` still ended up being a bit
slower. Not dramatically slower, but still noticably and unexpectedly.
As I'm not at all comfortable with Typed Racket I would appreciate if
someone could show how one would annotate the example minimally to give
the optimizer enough information to surpass Racket. As of this moment I
haven't really managed to see any improvement from using Typed Racket. It
cut down the time `divides?` needed to a few seconds more than Racket.
Otherwise, it had no effect (on the other example either).
As a point of curiosity; I had to work around the fact that apparently
there were not enough type annotations by wrapping the `for`s in functions
and typing them accordingly. Is there a better way to do this?
I'm currently trying to compare some performance between OCaml, C and
Racket and I'm currently using the aforementioned example.
Here are some timings:
|> time racket divides.rkt; time ./divides_c; time ./divides_ocaml
41666666583333333
racket divides.rkt 7.32s user 0.02s system 100% cpu 7.336 total
41666666583333333
./divides_c 0.49s user 0.00s system 99% cpu 0.488 total
41666666583333333
./divides_ocaml 0.75s user 0.00s system 99% cpu
The idea is to see how fast one can make the following:
#lang racket/base
(define (divisible-by? x d)
(= (modulo x d)
0))
(module+ main
(for/sum ([x (in-range 3 500000000)])
(if (x . divisible-by? . 3)
x
0))
)
On Mon, 24 Aug 2015, Pierpaolo Bernardi wrote:
On Mon, Aug 24, 2015 at 1:25 PM, Jens Axel Søgaard
<[email protected]> wrote:
It looks very odd to me.
Maybe this is due to calling TR functions from plain Racket?
--
You received this message because you are subscribed to the Google Groups "Racket
Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
