Re: [ELPA] New package: dired-duplicates

[Eli Zaretskii <eliz@gnu.org>]

> From: Philip Kaludercic <philipk@posteo.net>
> Cc: Visuwesh <visuweshm@gmail.com>,  h.judt@gmx.at,  emacs-devel@gnu.org
> Date: Wed, 01 Nov 2023 17:57:40 +0000
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I'd like to see the numbers which led to the conclusion that
> > performance was prohibitive.
> >
> > And even if the performance is indeed much worse, it could be a
> > fallback in case the program is not available -- which would IMO be
> > much better than simply failing to provide the functionality in that
> > case.
> 
> This is a cheap test on a 1.4GB ISO I had lying around:

Thanks.  But this is just a single large file, not a frequent use case
for this package.

> --8<---------------cut here---------------start------------->8---
> (benchmark-run 1
>   (with-temp-buffer
>     (insert-file-contents-literally "~/Downloads/haiku-r1beta4-x86_64-anyboot.iso")
>     (secure-hash 'sha512 (current-buffer))))
> ;; (44.389091035 1 1.5836082630000021)
> 
> (benchmark-run 1
>   (with-temp-buffer
>     (call-process "sha512sum" nil t nil (expand-file-name "~/Downloads/haiku-r1beta4-x86_64-anyboot.iso"))
>     (goto-char (point-min))
>     (and (looking-at (rx bos (+ alnum)))
> 	 (match-string 0))))
> ;; (5.155846791 0 0.0)
> --8<---------------cut here---------------end--------------->8---

And this is not the package doing its job, this is just a single task
the package does when looking for duplicates.  The numbers when
running the package with call-process replaced by secure-hash will
probably be different.