Hi,
Ludovic Courtès <l...@gnu.org> skribis:
> To my surprise, on a pure bignum microbenchmark, this is
> counterproductive:
I found out that I was comparing my own Guile build, which was against
the ‘libgc-back-pointers’ package, with that ‘guile-next’ build against
‘libgc’; no wonder mine was slower…
--8<---------------cut here---------------start------------->8---
$ cat ~/src/guile-debugging/bignum-finalizers.scm
(use-modules (ice-9 time))
(time
(let loop ((n (expt 2 18))
(i 1))
(unless (zero? n)
;; (display ".")
(loop (- n 1)
(logior 0 (ash i 1))))))
(format #t "heap size: ~a MiB~%"
(round
(/ (assoc-ref (gc-stats) 'heap-size) (expt 2. 20))))
--8<---------------cut here---------------end--------------->8---
There’s no noticeable difference on the microbenchmark when using the
same libgc both times, and there’s still ~2.5x difference when compiling
‘gnu/services/mail.scm’.
I went ahead and pushed the change as 00fbdfa7345765168e14438eed0b0b8c64c27ab9.
I did a full bootstrap build, which went fine and felt faster, though I
don’t have hard figures to compare to (110m user according to Bash’
‘time’ on my laptop).
Give it a spin and let me know!
Thanks,
Ludo’.
