[plt-scheme] redefining set!

Hey,

That's extremely interesting. I'm running mzscheme
directly. How do I disable "debug" in mzscheme then?

Or do you have a very fast machine (about 2 times faster
then mine)?

--Hans


Op 18/6/2007 schreef "Jens Axel Søgaard" <jensaxel at soegaard.net>:

>Hans Oesterholt-Dijkema skrev:
>> Hmm, I'm not sure if I'm going to win a lot with this
>> excersize:
>>
>>  > (define (f x) (if (> x 0) (begin (g x) (f (- x 1))) #t))
>>  > (define (g x) x)
>>  > (time (f 10000000))
>> cpu time: 1572 real time: 1572 gc time: 0
>> #t
>>  > (define v (vector g))
>>  > (define (h x) (if (> x 0) (begin ((vector-ref v 0) x) (h (- x 1))) #t))
>>  > (time (h 10000000))
>> cpu time: 2023 real time: 2033 gc time: 0   (123%)
>> #t
>>  > (time (h 10000000))
>> cpu time: 1903 real time: 1913 gc time: 0  (117%)
>> #t
>>  > (define k (make-hash-table))
>>  > (hash-table-put! k 'g g)
>>  > (define (l x) (if (> x 0) (begin ((hash-table-get k 'g) x) (l (- x
>> 1))) #t))
>>  > (time (l 10000000))
>> cpu time: 2113 real time: 2123 gc time: 0  (130%)
>>
>>  > (define-syntax q
>> (syntax-rules ()
>> ((_ g a1 ...) (g a1 ...))))
>>  > (define (z x) (if (> x 0) (begin (q g x) (z (- x 1))) #t))
>>  > (time (z 10000000))
>> cpu time: 1663 real time: 1663 gc time: 0  (100%)
>> #t
>>  > (time (f 10000000))
>> cpu time: 1632 real time: 1632 gc time: 0
>> #t
>
>Good idea to bechmark. Are you using DrScheme?
>
>Remember
>
>   (require mzscheme)
>
>at the top in order to help the inliner.
>
>Also disable debug-info in the language menu.
>
>
>(require mzscheme)
>
>(define (f x) (if (> x 0) (begin (g x) (f (- x 1))) #t))
>(define (g x) x)
>(time (f 10000000))
>
>(define v (vector g))
>(define (h x) (if (> x 0) (begin ((vector-ref v 0) x) (h (- x 1))) #t))
>  (time (h 10000000))
>
>(define k (make-hash-table))
>(hash-table-put! k 'g g)
>(define (l x) (if (> x 0) (begin ((hash-table-get k 'g) x) (l (- x 1))) #t))
>
>(define-syntax q
>   (syntax-rules ()
>     ((_ g a1 ...) (g a1 ...))))
>(define (z x) (if (> x 0) (begin (q g x) (z (- x 1))) #t))
>(time (z 10000000))
>(time (f 10000000))
>
>
>No (require mzscheme) and with debug:
>
>   cpu time: 2516 real time: 2640 gc time: 0
>   cpu time: 3187 real time: 3250 gc time: 0
>   cpu time: 3000 real time: 3015 gc time: 0
>   cpu time: 2562 real time: 2625 gc time: 0
>
>With (require mzscheme) and with debug:
>
>   cpu time: 1578 real time: 1672 gc time: 0
>   cpu time: 2172 real time: 2250 gc time: 0
>   cpu time: 1953 real time: 1954 gc time: 0
>   cpu time: 1625 real time: 1656 gc time: 0
>
>With (require mzscheme) and no debug:
>
>   cpu time: 750 real time: 813 gc time: 0
>   cpu time: 781 real time: 796 gc time: 0
>   cpu time: 735 real time: 735 gc time: 0
>   cpu time: 750 real time: 750 gc time: 0
>
>Now the times are almost identical.
>
>--
>Jens Axel Søgaard
>
>
>