bug#81525: 32.0.50; [PATCH] Performance improvement for rgrep's find command

Phil Sainty <[email protected]> writes:

> On 2026-07-31 20:13, Manuel Giraud wrote:
>> Thanks.  I have used your benchmark and FWIW, I don't see much
>> difference on a OpenBSD machine:
>
> Interesting.  Perhaps your version of find figures out that
> it can use more efficient matching in these cases (or just
> has a faster implementation of the -path matching).

Your interrogations drive me into more tests ;-) So yes, OpenBSD has its
own implementation of find but there is also a package with GNU find
(renamed gfind).  The version of GNU find, I have is:

find (GNU findutils) 4.10.0
Copyright (C) 2024 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Eric B. Decker, James Youngman, and Kevin Dalley.
Features enabled: D_TYPE O_NOFOLLOW(enabled) LEAF_OPTIMISATION FTS(FTS_CWDFD) CBO(level=1) 

Now, I have run your benchmark again like this:

(require 'grep)
(grep-compute-defaults)

(with-current-buffer (get-buffer-create "*result*")
  (erase-buffer)
  (dolist (find (list "find" "gfind"))
    (let ((grep-find-template
	   (format "time %s -H <D> <X> -type f <F> -print 2>/dev/null" find)))
      (dotimes (i 2)
	(shell-command (rgrep-default-command
			"ignore" "no-such-file" "$HOME"))
	(insert (format "%s#%d\n" find i))
	(insert-buffer-substring "*Shell Command Output*")))))

And here is the results, I get:

* Without your patch:
find#0
    0m30.76s real     0m03.45s user     0m15.64s system
find#1
    0m09.03s real     0m01.34s user     0m07.72s system
gfind#0
    0m02.25s real     0m01.33s user     0m00.91s system
gfind#1
    0m02.25s real     0m01.19s user     0m01.05s system

* With your patch:
find#0
    0m29.81s real     0m03.43s user     0m15.36s system
find#1
    0m08.93s real     0m01.52s user     0m07.32s system
gfind#0
    0m02.33s real     0m01.33s user     0m00.97s system
gfind#1
    0m02.25s real     0m01.23s user     0m01.05s system

Each run was done after a fresh reboot (I don't know how to flush the
buffer cache on OpenBSD :-/) so I think that each time the first run
with "find" is slower because of buffer cache's warming.

What I conclude from these results:

         - GNU find is faster than native find.
         
         - I still don't see any significant speed up with your patch
           (sorry).
-- 
Manuel Giraud