Re: Loading souce Elisp faster

[David Engster]

Richard Stallman writes:
>     > All we could potentially avoid with the proposal for utf-8 as default
>     > is the step of choosing the coding system heuristically.  This would
>     > not make it as fast as find-file-literally.  It would make it as fast
>     > as if you had a coding: tag on the first line.  How much speedup is
>     > that?
>
>     I wouldn't know how to test this without implementing it.
>
> It is simple to test it.  Put `-*-coding: utf-8;-*-' on the first line
> of the file, then visit it using find-file.  How fast is that?
> How does it compare, in time, with the two cases you tested?

I actually tried that, but it took *longer* with the "coding: utf-8;"
comment, which is why I thought that this is apparently not working and
some additional changes are needed first.

Here's what I tried: I took files.el from emacs/lisp and copied it to
files_utf8.el and added the "coding" comment there. Then I used this:

(setq filename "~/files_utf8.el")
(setq final 0)
(dotimes (i 1000)
  (let ((res
         (benchmark-run (find-file filename))))
    (setq final (+ final (car res)))
    (kill-buffer (find-buffer-visiting filename))))
(message "Result: %f" final)

Without the coding-comment, this takes ~7.5s, but *with* the
coding-comment it takes ~9.5s.

-David