Pierpaolo Bernardi <olopierpa@...> writes: > > On Tue, Dec 11, 2012 at 4:03 PM, daniel rupis > <danielrupistralizavez@...> wrote: > > > > I was comparing some code in Qi with that of sbcl, I posted a question in > > comp.lang.lisp asking for a way to improve the perfomance, WJ gave a typed > > racket version that was slower than sbcl and also much slower than cpp. > > The sbcl version is unsafe and uses numbers declared to be in a small range. > > To not compare apples to pears, please measure the version below which > uses unsafe features of racket similar to the ones in the sbcl > version. > > On my machine it produces: > > c:\Users\bernardip\Documents\Scheme>testp > 3340 > cpu time: 2594 real time: 2685 gc time: 0 > > Remember to generate an executable, to obtain the maximum speed. > > Alternatively, compare your racket version against sbcl with (declare > (optimize safety 3)) > > Cheers > P. > > ==== > > #lang racket > > (require racket/unsafe/ops) > > (define (divisible-rec i j) > (cond ((unsafe-fx= j 1) > #f) > ((unsafe-fx= 0 (unsafe-fxmodulo i j)) > #t) > (else > (divisible-rec i (unsafe-fx+ -1 j))))) > > (define (divisible n) > (divisible-rec n (unsafe-fx+ -1 n))) > > (define (total-primes k) > (for/sum ([n (in-range 2 (add1 k))]) > (if (divisible n) > 0 > 1))) > > (define (test) > (time (displayln (total-primes 30999)))) > > (test) > > ======== > ____________________ > Racket Users list: > http://lists.racket-lang.org/users > >
Comparison: better with 60999 to minimize any other small time not related to the computations. sbcl (time (totalprimes 60999)) Evaluation took: 20.394 seconds of real time 20.381273 seconds of total run time (20.377273 user, 0.004000 system) 99.94% CPU 42,720,745,799 processor cycles 0 bytes consed 6145 racket on the same machine ubuntu 12.04 user@ubuntu:~/lang/racket/racket$ uname -a Linux ubuntu 3.2.0-34-generic #53-Ubuntu SMP Thu Nov 15 10:48:16 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux Welcome to Racket v5.3.1. (define (test) (time (displayln (total-primes 60999))))> > > > > (test) 6145 cpu time: 39170 real time: 39156 gc time: 0 Using ubuntu 12.04 and racket ____________________ Racket Users list: http://lists.racket-lang.org/users
